feat: back up the phone's photos to a group, once a day on Wi-FiHEADmain

The Android application sends the photos taken on the phone to one folder of
one group chosen by the member (docs/MESHBAY_DESIGN.md §9.12). The phone lists
MediaStore, keeps a ledger of what was sent and hands each photo's bytes to the
page by an opaque token on the packaged origin; the page decides when a run is
due and uploads through the existing path, one photo at a time under a slot.

- Once a day from the last finished run, on an unmetered network only;
  "Back up now" asks first on mobile data. Leaving Wi-Fi stops after the file
  in flight.
- Photos already on the phone are sent by default, newest first, under
  <folder>/YYYY/MM; edits are sent beside the original as -edited-<date>.
- Additive by construction: nothing is ever deleted, renamed or replaced on
  the node, and a photo deleted on the node is not sent again.
- A confirmation names the group, owner, members, folder and size when the
  destination or starting point changes; a lasting refusal (disk full, folder
  read-only or gone, no longer a member) is said once and retried a day later.
- No ACCESS_MEDIA_LOCATION, so the platform redacts photo locations.
- A dataSync foreground service keeps a run going with the screen off.

HEIC/HEIF photos are sent but not shown in Photos yet (§15.2).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/app.js b/packages/meshbay-hub/src/meshbay_hub/static/app.js
index e2d5742..41a608f 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/app.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/app.js
@@ -904,6 +904,30 @@ function App() {
     pullOnce(user.userId).catch(() => {});
   }, [user, groups.length]);
 
+  // Photo backup (docs/MESHBAY_DESIGN.md §9.12), on the Android application
+  // only: loaded and started once signed in, stopped on sign-out. A run reads
+  // the live user and bundle key when it starts, never ones captured here.
+  const syncAccount = user ? user.username : null;
+  useEffect(() => {
+    if (!syncAccount || !platform.photoSync.available) return undefined;
+    let stop = null;
+    let gone = false;
+    import('./photo-sync.js').then((m) => {
+      if (gone) return;
+      m.startPhotoSync({
+        hub: HUB,
+        getUser: () => userRef.current,
+        getBundleKey: async () => {
+          const key = session.bundleKey || await _loadBundleKey();
+          if (key) session.bundleKey = key;
+          return key;
+        },
+      });
+      stop = m.stopPhotoSync;
+    }).catch((e) => console.warn('[MeshBay] photo backup did not load:', e.message));
+    return () => { gone = true; if (stop) stop(); };
+  }, [syncAccount]);
+
   // Saving the queue is a shell-level action because the queue is: the player
   // bar outlives every page, and the account it belongs to is here.
   const [saveQueue, setSaveQueue] = useState(null);