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/cli.py

@@ -12,6 +12,11 @@ Flask CLI commands for LIM backup and restore.
     flask instructions run [--count N] [--force]
     flask instructions status
 
+    flask owner show
+    flask owner set USERNAME
+    flask logs path [--tail N]
+    flask logs prune [--days N]
+
 `restore` is the path to use on a fresh Docker instance: no login required,
 and it works before any admin user exists.
 
@@ -267,6 +272,88 @@ def instructions_status():
                f"{summary['sets_missing_pdfs']} without a PDF")
 
 
+owner_cli = AppGroup('owner', help='Who owns this instance.')
+
+
+@owner_cli.command('show')
+def owner_show():
+    """Show the owner account (the only one who can read the logs)."""
+    from app.services.ownership import get_owner
+
+    owner = get_owner()
+    if owner is None:
+        click.secho('No users exist yet.', fg='yellow')
+        return
+    click.secho(f'Owner: {owner.username} <{owner.email}> (id {owner.id})',
+                fg='green')
+
+
+@owner_cli.command('set')
+@click.argument('username')
+def owner_set(username):
+    """Hand ownership to USERNAME (promotes them to admin if needed)."""
+    from app.models.user import User
+    from app.services.ownership import set_owner
+
+    user = User.query.filter_by(username=username).first()
+    if user is None:
+        click.secho(f'No user called {username!r}.', fg='red')
+        raise SystemExit(1)
+
+    set_owner(user)
+    click.secho(f'{user.username} is now the owner.', fg='green')
+
+
+logs_cli = AppGroup('logs', help='Application log file.')
+
+
+@logs_cli.command('path')
+@click.option('--tail', default=0, type=int,
+              help='Also print the last N lines.')
+def logs_path(tail):
+    """Where the log lives, and optionally its tail."""
+    import os
+
+    from flask import current_app
+
+    from app.services import logging_setup
+
+    path = logging_setup.log_path(current_app)
+    exists = os.path.isfile(path)
+    click.echo(f'  {path}')
+    click.echo(f'  exists: {exists}'
+               + (f'  size: {os.path.getsize(path)} bytes' if exists else ''))
+    click.echo(f'  handler active: {logging_setup.get_handler() is not None}')
+
+    if tail and exists:
+        entries, total = logging_setup.read_entries(path, max_entries=tail)
+        click.echo(f'\n  last {len(entries)} of {total} entries:\n')
+        for entry in entries:
+            click.echo(f"  {entry['time']} {entry['level']:<8} "
+                       f"{entry['logger']} | {entry['message']}")
+
+
+@logs_cli.command('prune')
+@click.option('--days', default=None, type=int,
+              help='Override the configured retention.')
+def logs_prune(days):
+    """Delete old Brickset API call records."""
+    from app.models.api_call import BricksetApiCall
+    from app.models.site_setting import SiteSetting
+
+    if days is None:
+        try:
+            days = int(SiteSetting.get('api_log_retention_days', '90'))
+        except (TypeError, ValueError):
+            days = 90
+
+    removed = BricksetApiCall.prune(days)
+    click.secho(f'Removed {removed} record(s) older than {days} days.',
+                fg='green')
+
+
 def register_cli(app):
     app.cli.add_command(backup_cli)
     app.cli.add_command(instructions_cli)
+    app.cli.add_command(owner_cli)
+    app.cli.add_command(logs_cli)