Add owner-only logging and Brickset API call tracking

LIM configured no logging at all, so the instruction fetcher had no trail to follow. Adds a rotating file handler on the root logger plus two owner-only admin pages.

- Admin > Logs: filter by level, source and text; tracebacks kept with their error; auto-refresh, raw download, rotated-file browsing and rotate-now

- Admin > Logs > Brickset API calls: every outbound call recorded with method, params, caller, duration, result count and error, plus daily quota accounting (only getSets counts) and a comparison against getKeyUsageStats

- New owner concept (services/ownership.py): a single account, distinct from is_admin, since these pages expose other admins activity. Defaults to the first admin; flask owner show/set to change

- Services now log through module loggers; retention setting and pruning for call records

- New CLI: flask owner show/set, flask logs path/prune

- New table brickset_api_calls, created automatically at boot; LOG_* env vars, /data/logs in Docker

app/services/fetch_worker.py

@@ -18,10 +18,13 @@ with `flask instructions run` instead.
 Created by: Jess Rogerson (yelling commands at Claude.AI)
 """
 
+import logging
 import os
 import sys
 import threading
 
+logger = logging.getLogger(__name__)
+
 _thread = None
 _stop = threading.Event()
 _lock = threading.Lock()
@@ -38,7 +41,7 @@ def _is_cli_command():
 def start(app):
     """Start the ticker unless it's disabled or already running."""
     if not app.config.get('INSTRUCTION_FETCH_WORKER', True):
-        app.logger.info('Instruction fetch worker disabled by config')
+        logger.info('Instruction fetch worker disabled by config')
         return False
 
     # `flask instructions run`, `flask backup restore` and friends shouldn't
@@ -61,7 +64,8 @@ def start(app):
                                    daemon=True)
         _thread.start()
 
-    app.logger.info('Instruction fetch worker started')
+    logger.info('Instruction fetch worker started (tick %ss)',
+                app.config.get('INSTRUCTION_FETCH_TICK_SECONDS', 20))
     return True
 
 
@@ -86,7 +90,7 @@ def _loop(app):
             with app.app_context():
                 fetcher.run_one()
         except Exception:
-            app.logger.exception('Instruction fetch worker tick failed')
+            logger.exception('Instruction fetch worker tick failed')
 
 
 def run_once_async(app, force=False):
@@ -102,7 +106,7 @@ def run_once_async(app, force=False):
                 from app.services import instruction_fetcher as fetcher
                 fetcher.run_one(force=force)
         except Exception:
-            app.logger.exception('Manual instruction fetch failed')
+            logger.exception('Manual instruction fetch failed')
 
     thread = threading.Thread(target=_work, name='lim-fetch-once', daemon=True)
     thread.start()