diff --git a/public/orient-debug.html b/public/orient-debug.html
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+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="utf-8" />
+<meta name="viewport" content="width=device-width, initial-scale=1, viewport-fit=cover, maximum-scale=1" />
+<title>Newbury — orientation debug</title>
+<style>
+  :root { --ink:#e8eaf2; --dim:#8a93ad; --cyan:#51eaf1; --green:#4ade80; --amber:#fbbf24; --red:#f65151;
+    --panel:rgba(8,10,16,0.9); }
+  * { box-sizing:border-box; }
+  html,body { margin:0; height:100%; background:#05060a; color:var(--ink);
+    font-family:'Inter',system-ui,sans-serif; overflow:hidden; }
+  #video { position:absolute; top:50%; left:50%; transform:translate(-50%,-50%); }
+  #three,#overlay { position:absolute; top:50%; left:50%; transform:translate(-50%,-50%); }
+  #overlay { pointer-events:none; }
+
+  #hud { position:fixed; left:10px; top:calc(10px + env(safe-area-inset-top)); padding:11px 13px;
+    background:var(--panel); border:1px solid rgba(255,255,255,0.1); border-radius:12px;
+    font-family:ui-monospace,monospace; font-size:11px; line-height:1.65; backdrop-filter:blur(8px); max-width:88vw; }
+  #hud h3 { margin:0 0 6px; font-family:'Inter',sans-serif; font-size:12px; }
+  #hud .row { display:flex; gap:8px; }
+  #hud .lab { color:var(--dim); width:66px; display:inline-block; }
+  #hud .v { font-weight:600; }
+  .rgb-x{color:#ff6b6b}.rgb-y{color:#7CFF6b}.rgb-z{color:#6b9cff}
+
+  #controls { position:fixed; left:50%; bottom:calc(14px + env(safe-area-inset-bottom));
+    transform:translateX(-50%); display:flex; gap:8px; flex-wrap:wrap; justify-content:center; width:94vw; }
+  #controls button { border:0; border-radius:10px; padding:12px 14px; font-size:13px; font-weight:600;
+    cursor:pointer; background:#1a2033; color:var(--ink); flex:1; min-width:88px; max-width:150px; }
+  #controls button.rec { background:var(--red); color:#fff; }
+  #controls button.primary { background:linear-gradient(135deg,#529eff,#51eaf1); color:#06121f; }
+  #count { position:fixed; left:50%; bottom:calc(66px + env(safe-area-inset-bottom)); transform:translateX(-50%);
+    font-family:ui-monospace,monospace; font-size:12px; color:var(--dim); background:var(--panel);
+    padding:5px 12px; border-radius:8px; }
+
+  #logout { position:fixed; inset:0; background:#080a12; padding:16px; display:none; flex-direction:column; gap:10px; z-index:20; }
+  #logout.show { display:flex; }
+  #logout textarea { flex:1; width:100%; background:#0e1220; color:var(--ink); border:1px solid #26304a;
+    border-radius:10px; padding:12px; font-family:ui-monospace,monospace; font-size:11px; resize:none; }
+  #logout .row { display:flex; gap:8px; }
+  #logout button { flex:1; border:0; border-radius:10px; padding:13px; font-size:14px; font-weight:600; cursor:pointer; }
+  #copyBtn { background:linear-gradient(135deg,#529eff,#51eaf1); color:#06121f; }
+  #closeBtn { background:#1a2033; color:var(--ink); }
+  #copied { text-align:center; color:var(--green); font-size:12px; height:14px; }
+
+  #start { position:fixed; inset:0; display:flex; flex-direction:column; align-items:center; justify-content:center;
+    gap:16px; text-align:center; padding:26px; background:radial-gradient(circle at 50% 40%,#141a2b,#05060a 72%); }
+  #start h1 { font-size:22px; margin:0; } #start p { color:var(--dim); max-width:34ch; line-height:1.6; font-size:13.5px; margin:0; }
+  #go { border:0; cursor:pointer; font-size:16px; font-weight:600; color:#06121f;
+    background:linear-gradient(135deg,#529eff,#51eaf1); padding:14px 32px; border-radius:999px; }
+  #err { color:var(--red); font-size:12.5px; max-width:34ch; }
+  .hidden { display:none !important; }
+</style>
+</head>
+<body>
+  <video id="video" playsinline muted autoplay></video>
+  <canvas id="three"></canvas>
+  <canvas id="overlay"></canvas>
+
+  <div id="hud" class="hidden">
+    <h3>Orientation debug</h3>
+    <div class="row"><span class="lab">marker</span><span class="v" id="dId">—</span></div>
+    <div class="row"><span class="lab">RAW posit</span><span class="v" id="dRaw">—</span></div>
+    <div class="row"><span class="lab">RENDER</span><span class="v" id="dRender">—</span></div>
+    <div class="row"><span class="lab">gyro</span><span class="v" id="dGyro">—</span></div>
+    <div class="row"><span class="lab" style="color:var(--amber)">watch</span><span id="dHint" style="color:var(--amber)">tilt phone up = pitch should ↑</span></div>
+  </div>
+
+  <div id="count" class="hidden">not recording</div>
+  <div id="controls" class="hidden">
+    <button id="recBtn">● Record</button>
+    <button id="markBtn">Mark</button>
+    <button id="viewBtn" class="primary">Copy log</button>
+  </div>
+
+  <div id="logout">
+    <div id="copied"></div>
+    <textarea id="logText" readonly></textarea>
+    <div class="row">
+      <button id="copyBtn">Copy to clipboard</button>
+      <button id="closeBtn">Back</button>
+    </div>
+  </div>
+
+  <div id="start">
+    <h1>Orientation debug</h1>
+    <p>Shows raw POS-IT angles vs what we render, plus a 3D gizmo on the marker. Tilt & rotate the phone; the RGB axes should stay glued to the marker. Record and send me the log.</p>
+    <button id="go">Start camera</button>
+    <div id="err"></div>
+  </div>
+
+  <script src="vendor/cv.js"></script>
+  <script src="vendor/svd.js"></script>
+  <script src="vendor/posit1.js"></script>
+  <script src="vendor/aruco.js"></script>
+  <script src="vendor/dictionaries/aruco_4x4_1000.js"></script>
+  <script type="importmap">
+  { "imports": {
+      "three": "https://cdn.jsdelivr.net/npm/three@0.160.0/build/three.module.js",
+      "three/addons/": "https://cdn.jsdelivr.net/npm/three@0.160.0/examples/jsm/"
+  } }
+  </script>
+  <script type="module">
+    import * as THREE from 'three';
+    import { TunedDetector, MarkerTracker } from './js/detect-tuned.js?v=1';
+
+    const $ = (id) => document.getElementById(id);
+    const video = $('video'), canvas = $('three'), overlay = $('overlay');
+    const octx = overlay.getContext('2d');
+    const grab = document.createElement('canvas'), gctx = grab.getContext('2d', { willReadFrequently: true });
+    const MARKER_SIZE_MM = 96;
+
+    let detector, tracker, posit, focalPx = 0, running = false;
+    let recording = false, log = [], frameN = 0;
+    let gyro = { alpha: null, beta: null, gamma: null };
+
+    // ---- three.js: mirror ar-head EXACTLY, but draw an AXIS GIZMO not a ghost ----
+    const renderer = new THREE.WebGLRenderer({ canvas, alpha: true, antialias: true });
+    renderer.setClearColor(0x000000, 0);
+    const scene = new THREE.Scene();
+    scene.add(new THREE.AmbientLight(0xffffff, 1.2));
+    let camera = new THREE.PerspectiveCamera(50, 1, 1, 5000);
+
+    // anchor object driven by pose (exactly like ar-head)
+    const anchor = new THREE.Object3D();
+    anchor.matrixAutoUpdate = false;
+    scene.add(anchor);
+
+    // A big RGB axis gizmo + an "UP" arrow, parented to anchor.
+    const gizmo = new THREE.AxesHelper(MARKER_SIZE_MM * 1.2);
+    anchor.add(gizmo);
+    // a distinct arrow pointing along marker normal (local +Z) so we see "up off table"
+    const arrowMat = new THREE.MeshBasicMaterial({ color: 0x51eaf1 });
+    const arrow = new THREE.Mesh(new THREE.ConeGeometry(10, 40, 12), arrowMat);
+    arrow.position.set(0, 0, MARKER_SIZE_MM); // +Z = marker normal
+    arrow.rotation.x = Math.PI / 2;
+    anchor.add(arrow);
+    anchor.visible = false;
+
+    const flip = new THREE.Matrix4().makeScale(1, -1, -1);
+    const poseMatrix = new THREE.Matrix4();
+
+    function centredCorners(m, w, h) { return m.corners.map((c) => ({ x: c.x - w / 2, y: h / 2 - c.y })); }
+
+    function applyPose(m) {
+      const pose = posit.pose(centredCorners(m, grab.width, grab.height));
+      if (!pose) return null;
+      const R = pose.bestRotation, t = pose.bestTranslation;
+      poseMatrix.set(
+        R[0][0], R[0][1], R[0][2], t[0],
+        R[1][0], R[1][1], R[1][2], t[1],
+        R[2][0], R[2][1], R[2][2], t[2],
+        0, 0, 0, 1
+      );
+      poseMatrix.premultiply(flip); // F*M  (ar-head convention)
+      anchor.matrix.copy(poseMatrix);
+      anchor.matrixWorldNeedsUpdate = true;
+
+      // raw posit euler (before flip) and rendered euler (after flip)
+      const rawM = new THREE.Matrix4().set(
+        R[0][0], R[0][1], R[0][2], 0, R[1][0], R[1][1], R[1][2], 0, R[2][0], R[2][1], R[2][2], 0, 0,0,0,1);
+      const rawE = new THREE.Euler().setFromRotationMatrix(rawM, 'YXZ');
+      const renM = poseMatrix.clone(); renM.setPosition(0,0,0);
+      const renE = new THREE.Euler().setFromRotationMatrix(renM, 'YXZ');
+      return {
+        dist: Math.hypot(t[0], t[1], t[2]),
+        raw: { yaw: deg(rawE.y), pitch: deg(rawE.x), roll: deg(rawE.z) },
+        ren: { yaw: deg(renE.y), pitch: deg(renE.x), roll: deg(renE.z) },
+      };
+    }
+    const deg = (r) => Math.round(r * 180 / Math.PI);
+
+    function sizeAll() {
+      const vw = video.videoWidth, vh = video.videoHeight; if (!vw) return;
+      grab.width = vw; grab.height = vh;
+      const scale = Math.max(innerWidth / vw, innerHeight / vh);
+      const dw = vw * scale, dh = vh * scale;
+      for (const el of [video, canvas, overlay]) { el.style.width = dw + 'px'; el.style.height = dh + 'px'; }
+      renderer.setPixelRatio(Math.min(devicePixelRatio, 2)); renderer.setSize(dw, dh, false);
+      overlay.width = dw; overlay.height = dh;
+      focalPx = vw;
+      const fovY = 2 * Math.atan((vh / 2) / focalPx) * (180 / Math.PI);
+      camera.fov = fovY; camera.aspect = dw / dh; camera.updateProjectionMatrix();
+      posit = new POS.Posit(MARKER_SIZE_MM, focalPx);
+    }
+
+    async function start() {
+      $('err').textContent = '';
+      try {
+        const stream = await navigator.mediaDevices.getUserMedia({
+          video: { facingMode: { ideal: 'environment' }, width: { ideal: 1280 }, height: { ideal: 720 } }, audio: false });
+        video.srcObject = stream; await video.play();
+      } catch (e) { $('err').textContent = 'Camera error: ' + (e.message || e.name); return; }
+      detector = new TunedDetector({ dictionaryName: 'ARUCO_4X4_1000' }).setPreset('forgiving');
+      tracker = new MarkerTracker({ coastMs: 150, smooth: true });
+      // device orientation (gyro) — needs permission on iOS
+      if (typeof DeviceOrientationEvent !== 'undefined' && DeviceOrientationEvent.requestPermission) {
+        try { await DeviceOrientationEvent.requestPermission(); } catch (_) {}
+      }
+      addEventListener('deviceorientation', (e) => { gyro = { alpha: e.alpha, beta: e.beta, gamma: e.gamma }; });
+      await new Promise((r) => { if (video.readyState >= 2) r(); else video.onloadeddata = () => r(); });
+      sizeAll(); addEventListener('resize', sizeAll);
+      $('start').classList.add('hidden');
+      for (const id of ['hud','count','controls']) $(id).classList.remove('hidden');
+      running = true; requestAnimationFrame(loop);
+    }
+
+    const sx = () => overlay.width / grab.width, sy = () => overlay.height / grab.height;
+
+    function loop(now) {
+      if (!running) return; requestAnimationFrame(loop);
+      if (video.readyState < 2 || !grab.width) return;
+      gctx.drawImage(video, 0, 0, grab.width, grab.height);
+      const img = gctx.getImageData(0, 0, grab.width, grab.height);
+      let raw = []; try { raw = detector.detect(img, { width: grab.width, height: grab.height }); } catch (_) {}
+      const markers = tracker.update(raw, now);
+      octx.clearRect(0, 0, overlay.width, overlay.height);
+
+      let main = markers[0] || null;
+      if (main) {
+        // draw outline + corner numbers
+        octx.strokeStyle = '#51eaf1'; octx.lineWidth = 2; octx.beginPath();
+        main.corners.forEach((p, i) => { const x = p.x*sx(), y = p.y*sy(); i ? octx.lineTo(x,y) : octx.moveTo(x,y); });
+        octx.closePath(); octx.stroke();
+        main.corners.forEach((p, i) => {
+          const x = p.x*sx(), y = p.y*sy();
+          octx.fillStyle = ['#fff','#ffd24a','#ff8a3a','#ff5a5a'][i];
+          octx.beginPath(); octx.arc(x, y, 6, 0, 7); octx.fill();
+          octx.fillStyle = '#000'; octx.font = 'bold 10px monospace'; octx.fillText(i, x-3, y+3);
+        });
+
+        const res = applyPose(main);
+        if (res) {
+          anchor.visible = true;
+          $('dId').textContent = 'id ' + main.id + (main.coasting ? ' coast' : '');
+          $('dRaw').innerHTML = fmt(res.raw);
+          $('dRender').innerHTML = fmt(res.ren);
+          $('dGyro').textContent = gyro.beta != null
+            ? `β${Math.round(gyro.beta)} γ${Math.round(gyro.gamma)} α${Math.round(gyro.alpha)}` : 'n/a';
+
+          if (recording) {
+            frameN++;
+            if (frameN % 3 === 0) {
+              log.push({ t: Math.round(now), id: main.id, dist: Math.round(res.dist),
+                raw: res.raw, ren: res.ren, gyro: { b: r1(gyro.beta), g: r1(gyro.gamma), a: r1(gyro.alpha) } });
+              $('count').textContent = `● REC · ${log.length}`;
+            }
+          }
+        }
+      } else {
+        anchor.visible = false; $('dId').textContent = 'none';
+      }
+      renderer.render(scene, camera);
+    }
+    function r1(v){ return v==null?null:Math.round(v); }
+    function fmt(a){ return `<span class="rgb-y">P${a.pitch}</span> <span class="rgb-z">R${a.roll}</span> <span class="rgb-x">Y${a.yaw}</span>`; }
+
+    function buildLog() {
+      const L = [];
+      L.push('=== NEWBURY ORIENTATION LOG ===');
+      L.push('conversion: F*M (premultiply flip)  marker:' + MARKER_SIZE_MM + 'mm  cam:' + grab.width + 'x' + grab.height);
+      L.push('cols: t,id,dist, RAW(pitch,roll,yaw), RENDER(pitch,roll,yaw), GYRO(beta,gamma,alpha)');
+      L.push('gyro beta=front/back tilt, gamma=left/right tilt, alpha=compass');
+      L.push('samples:' + log.length);
+      L.push('');
+      for (const r of log) {
+        L.push([r.t, r.id, r.dist,
+          'RAW', r.raw.pitch, r.raw.roll, r.raw.yaw,
+          'REN', r.ren.pitch, r.ren.roll, r.ren.yaw,
+          'GYRO', r.gyro.b, r.gyro.g, r.gyro.a].join(','));
+      }
+      return L.join('\n');
+    }
+
+    $('recBtn').addEventListener('click', () => {
+      recording = !recording;
+      $('recBtn').classList.toggle('rec', recording);
+      $('recBtn').textContent = recording ? '■ Stop' : '● Record';
+      if (recording) { log = []; $('count').textContent = '● REC · 0'; }
+    });
+    $('markBtn').addEventListener('click', () => { log.push({ t: Math.round(performance.now()), mark: true, raw:{}, ren:{}, gyro:{} }); });
+    $('viewBtn').addEventListener('click', () => { $('logText').value = buildLog(); $('logout').classList.add('show'); });
+    $('copyBtn').addEventListener('click', async () => {
+      try { await navigator.clipboard.writeText($('logText').value); $('copied').textContent = 'Copied!'; }
+      catch (_) { $('logText').select(); $('copied').textContent = 'Long-press → Copy'; }
+    });
+    $('closeBtn').addEventListener('click', () => $('logout').classList.remove('show'));
+    $('go').addEventListener('click', start);
+  </script>
+</body>
+</html>
