Admin: add Garmin sync status panel

New /api/admin/garmin-sync (GET) and /api/admin/garmin-sync/run (POST)
endpoints mirror the Strava equivalents, reading _garmin_sync_status.json
per user and exposing a run-now button. Admin page shows the Garmin table
below the Strava one, with auth_error/api_error/ok badges and live polling
while a sync is running.

bincio/serve/deps.py

@@ -43,6 +43,8 @@ sync_secret: str = ""
 _db = None
 _strava_sync_running = False
 _strava_sync_lock = threading.Lock()
+_garmin_sync_running = False
+_garmin_sync_lock = threading.Lock()
 
 # ── Constants ─────────────────────────────────────────────────────────────────
 

bincio/serve/routers/admin.py

@@ -585,6 +585,74 @@ async def admin_strava_sync_run(
     return JSONResponse({"ok": True}, status_code=202)
 
 
+@router.get("/api/admin/garmin-sync")
+async def admin_garmin_sync_status(
+    bincio_session: str | None = Cookie(default=None),
+) -> JSONResponse:
+    """Return per-user Garmin sync status for the admin panel."""
+    deps._require_admin(bincio_session)
+    root = deps._get_data_dir()
+    users = []
+    for cf in sorted(root.glob("*/garmin_creds.json")):
+        user_dir = cf.parent
+        handle = user_dir.name
+
+        run_status: str | None = None
+        run_imported = 0
+        run_errors = 0
+        run_error_message: str | None = None
+        last_run: str | None = None
+        status_path = user_dir / "_garmin_sync_status.json"
+        if status_path.exists():
+            try:
+                ss = json.loads(status_path.read_text(encoding="utf-8"))
+                run_status = ss.get("status")
+                run_imported = ss.get("imported", 0)
+                run_errors = ss.get("errors", 0)
+                run_error_message = ss.get("error_message")
+                last_run = ss.get("last_run")
+            except (OSError, json.JSONDecodeError):
+                pass
+
+        users.append({
+            "handle": handle,
+            "run_status": run_status,
+            "run_imported": run_imported,
+            "run_errors": run_errors,
+            "run_error_message": run_error_message,
+            "last_run": last_run,
+        })
+
+    return JSONResponse({"running": deps._garmin_sync_running, "users": users})
+
+
+@router.post("/api/admin/garmin-sync/run")
+async def admin_garmin_sync_run(
+    bincio_session: str | None = Cookie(default=None),
+) -> JSONResponse:
+    """Trigger an immediate Garmin sync for all users (admin only)."""
+    deps._require_admin(bincio_session)
+    with deps._garmin_sync_lock:
+        if deps._garmin_sync_running:
+            raise HTTPException(409, "Sync already running")
+        deps._garmin_sync_running = True
+
+    def _run() -> None:
+        try:
+            from bincio.sync_garmin import sync_all
+            results = sync_all(deps._get_data_dir())
+            total_new = sum(n for n, _ in results.values())
+            if total_new > 0:
+                tasks._site_rebuild_event.set()
+        except Exception:
+            log.exception("admin_garmin_sync_run: unexpected error")
+        finally:
+            deps._garmin_sync_running = False
+
+    threading.Thread(target=_run, daemon=True, name="admin-garmin-sync").start()
+    return JSONResponse({"ok": True}, status_code=202)
+
+
 @router.post("/api/admin/users/{handle}/recompute-elevation")
 async def admin_recompute_elevation(
     handle: str,

site/src/pages/admin/index.astro

@@ -57,6 +57,29 @@ import Base from '../../layouts/Base.astro';
       <p id="strava-sync-running-note" class="text-xs text-blue-400 mt-2 hidden">Sync running… refreshing every 3 s</p>
     </div>
 
+    <div class="mt-10">
+      <div class="flex items-center justify-between mb-3">
+        <h2 class="text-sm font-semibold text-zinc-400 uppercase tracking-wider">Garmin Sync</h2>
+        <button id="garmin-run-btn" class="text-xs px-3 py-1.5 rounded-lg bg-zinc-800 hover:bg-blue-900 hover:text-blue-300 text-zinc-400 transition-colors">Run sync now</button>
+      </div>
+      <div class="overflow-x-auto rounded-lg border border-zinc-800">
+        <table class="w-full text-sm">
+          <thead>
+            <tr class="text-left text-zinc-500 text-xs border-b border-zinc-800">
+              <th class="px-4 py-2 font-medium">Handle</th>
+              <th class="px-4 py-2 font-medium text-right">Imported (last run)</th>
+              <th class="px-4 py-2 font-medium">Last run</th>
+              <th class="px-4 py-2 font-medium">Status</th>
+            </tr>
+          </thead>
+          <tbody id="garmin-sync-list">
+            <tr><td colspan="4" class="px-4 py-6 text-zinc-500 text-center">Loading…</td></tr>
+          </tbody>
+        </table>
+      </div>
+      <p id="garmin-sync-running-note" class="text-xs text-blue-400 mt-2 hidden">Sync running… refreshing every 3 s</p>
+    </div>
+
     <!-- Re-extract progress modal -->
     <dialog id="reextract-dialog" class="rounded-xl bg-zinc-900 border border-zinc-700 p-6 text-white max-w-2xl w-full backdrop:bg-black/60">
       <div class="flex items-center justify-between mb-4">
@@ -613,6 +636,89 @@ import Base from '../../layouts/Base.astro';
     }
   });
 
+  // ── Garmin sync ──────────────────────────────────────────────────────────────
+
+  const garminTbody   = document.getElementById('garmin-sync-list')!;
+  const garminRunBtn  = document.getElementById('garmin-run-btn') as HTMLButtonElement;
+  const garminRunNote = document.getElementById('garmin-sync-running-note')!;
+  let garminPollTimer: ReturnType<typeof setInterval> | null = null;
+
+  function garminStatusBadge(status: string | null, errMsg: string | null): string {
+    if (!status) return '<span class="text-xs text-zinc-500">never run</span>';
+    const map: Record<string, [string, string]> = {
+      ok:             ['text-green-400', 'OK'],
+      no_credentials: ['text-amber-400', 'No credentials'],
+      auth_error:     ['text-red-400',   'Auth error'],
+      api_error:      ['text-red-400',   'API error'],
+    };
+    const [color, label] = map[status] ?? ['text-zinc-400', status];
+    const detail = errMsg
+      ? `<span class="block text-zinc-500 text-xs truncate max-w-xs" title="${errMsg.replace(/"/g, '&quot;')}">${errMsg.slice(0, 80)}</span>`
+      : '';
+    return `<span class="${color} font-medium text-xs">${label}</span>${detail}`;
+  }
+
+  async function loadGarminSync() {
+    try {
+      const r = await fetch('/api/admin/garmin-sync', { credentials: 'include' });
+      if (!r.ok) {
+        garminTbody.innerHTML = `<tr><td colspan="4" class="px-4 py-4 text-red-400 text-center">Error ${r.status}</td></tr>`;
+        return;
+      }
+      const { running, users } = await r.json();
+
+      if (running) {
+        garminRunBtn.disabled = true;
+        garminRunBtn.textContent = 'Running…';
+        garminRunNote.classList.remove('hidden');
+        if (!garminPollTimer) {
+          garminPollTimer = setInterval(loadGarminSync, 3000);
+        }
+      } else {
+        garminRunBtn.disabled = false;
+        garminRunBtn.textContent = 'Run sync now';
+        garminRunNote.classList.add('hidden');
+        if (garminPollTimer) { clearInterval(garminPollTimer); garminPollTimer = null; }
+      }
+
+      if (!users.length) {
+        garminTbody.innerHTML = '<tr><td colspan="4" class="px-4 py-6 text-zinc-500 text-center">No users with Garmin connected.</td></tr>';
+        return;
+      }
+
+      garminTbody.innerHTML = users.map((u: any) => `
+        <tr class="border-b border-zinc-800/50">
+          <td class="px-4 py-3 text-white font-mono text-xs">@${u.handle}</td>
+          <td class="px-4 py-3 text-right text-zinc-300 tabular-nums">${u.run_imported ?? '—'}</td>
+          <td class="px-4 py-3 text-zinc-400 text-xs">${fmtDate(u.last_run)}</td>
+          <td class="px-4 py-3">${garminStatusBadge(u.run_status, u.run_error_message)}</td>
+        </tr>`).join('');
+    } catch (err) {
+      garminTbody.innerHTML = `<tr><td colspan="4" class="px-4 py-4 text-red-400 text-center">${String(err)}</td></tr>`;
+    }
+  }
+
+  garminRunBtn.addEventListener('click', async () => {
+    garminRunBtn.disabled = true;
+    garminRunBtn.textContent = 'Starting…';
+    try {
+      const r = await fetch('/api/admin/garmin-sync/run', { method: 'POST', credentials: 'include' });
+      if (r.ok) {
+        await loadGarminSync();
+      } else {
+        const d = await r.json().catch(() => ({}));
+        garminRunBtn.disabled = false;
+        garminRunBtn.textContent = 'Error: ' + (d.detail ?? r.status);
+        garminRunBtn.classList.add('text-red-400');
+      }
+    } catch {
+      garminRunBtn.disabled = false;
+      garminRunBtn.textContent = 'Error';
+      garminRunBtn.classList.add('text-red-400');
+    }
+  });
+
   load();
   loadSync();
+  loadGarminSync();
 </script>