feat: Phase 10b — Self-service UI (group create/join, upload, IndexedDB, search)

Six self-service features for the web SPA:
- Group creation UI with GEK auto-generation (AES-256-GCM ECIES)
- Member management + invite by username (GEK wrapping for invitee)
- Open group self-join flow (POST /v1/groups/{id}/join)
- File upload client→node (FILE_UPLOAD MNP type, .uploads/ staging)
- IndexedDB caching of group file indexes (instant display on revisit)
- Cross-group file search (SearchPage, pure client-side on cached indexes)

11 new tests (166 total): 8 group self-service + 3 AES GEK wrap/unwrap.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 76 insertions, 2 deletions

diff --git a/devel-phases-next.md b/devel-phases-next.md
index cccce44..3e49f19 100644
--- a/devel-phases-next.md
+++ b/devel-phases-next.md
@@ -1,6 +1,6 @@
 # MeshBay — Next Implementation Phases
 
-> Base: Phases 1–10 complete (except 10.9 → Phase 13). 155 tests. Web SPA + admin panel live on meshbay.org.
+> Base: Phases 1–10b complete (except 10.9 → Phase 13). 166 tests. Web SPA + admin panel + self-service UI live on meshbay.org.
 > Architecture reference: docs/meshbay-draft-v4.md
 > First security review: first-review.md (2026-08-10)
 
@@ -202,7 +202,7 @@ ICE/STUN handles all tested NAT types automatically.
 
 ## Phase 10 — meshbay.org site + admin/moderation UI
 
-Commit: 8fa298e (10.1–10.4), pending (10.5–10.8, 10.10) — 155 tests.
+Commit: 8fa298e (10.1–10.4), 022da76 (10.5–10.10) — 155 tests.
 
 **Objective:** meshbay.org becomes both a production hub and the project's public
 website, with admin/moderation interfaces and user-facing features.
@@ -331,6 +331,80 @@ same GEK bundles, same storage). Purpose: load distribution via DNS round-robin.
 
 ---
 
+## Phase 10b — Self-service UI + client-side features
+
+Pending commit — 166 tests.
+
+**Objective:** make the web SPA fully self-service — users can create groups,
+manage members, join open groups, upload files, and search across all cached
+group file indexes. No admin intervention needed for basic operations.
+
+### Self-service features
+
+| # | Component | Status |
+|---|---|---|
+| 10b.1 | Group creation UI (CreateGroupPage) | ✅ |
+| 10b.2 | Member management + invite (MembersPanel) | ✅ |
+| 10b.3 | Group join flow (open groups self-join) | ✅ |
+| 10b.4 | File upload (client → node via MNP FILE_UPLOAD) | ✅ |
+| 10b.5 | IndexedDB caching (group file indexes cached locally) | ✅ |
+| 10b.6 | Cross-group file search (SearchPage — client-side, no hub) | ✅ |
+
+### New API endpoints (10b.1–10b.3)
+
+| Method | Path | Auth | Description |
+|---|---|---|---|
+| POST | `/v1/groups` | Access token | Create a new group (name, visibility, join_policy) |
+| GET | `/v1/groups/{id}/members` | Access token | List group members (requires membership) |
+| POST | `/v1/groups/{id}/join` | Access token | Self-join open group (checks join_policy) |
+| POST | `/v1/groups/{id}/members/{username}/gek` | Access token | Store GEK bundle for invitee |
+| GET | `/v1/groups/{id}/gek` | Access token | Get own GEK bundle (for wrapping) |
+
+### New MNP message types (10b.4)
+
+| Type | Direction | Description |
+|---|---|---|
+| `file_upload` | client → node | Push encrypted file chunk (filename, chunk_index, total_chunks, data) |
+| `file_upload_ack` | node → client | Acknowledge chunk receipt |
+
+Node stores uploads in `shared_root/.uploads/` as `.part` files during transfer,
+renames to final location on last chunk. Filename sanitized (no path traversal).
+
+### Browser crypto additions (10b.2)
+
+AES-256-GCM ECIES variant for GEK wrapping in browsers. WebCrypto does not
+support ChaCha20-Poly1305, so a parallel ECIES scheme uses AES-256-GCM with
+a distinct HKDF info string (`meshbay:gek_wrap:v1:aes` vs `meshbay:gek_wrap:v1`).
+Both Python and browser implement the AES variant for interop.
+
+Functions added to `crypto.js`: `generateGEK()`, `wrapGEK()`, `unwrapGEK()`,
+`encryptChunk()`, `b64encode()`.
+
+Functions added to `crypto.py`: `wrap_gek_aes()`, `unwrap_gek_aes()`.
+
+### IndexedDB caching (10b.5)
+
+When a group's file index is fetched from a node, it is cached in IndexedDB
+(`meshbay` database, `group_indexes` store). On subsequent visits, cached
+entries are shown immediately while the live connection is established. This
+gives instant file list display even before WebRTC connects.
+
+Cache key: `groupId`. Stored: `{ groupId, groupName, entries[], cachedAt }`.
+Best-effort — failures are silently ignored.
+
+### Cross-group file search (10b.6)
+
+SearchPage component at `#/search`. Searches file names and paths across ALL
+cached group indexes in IndexedDB. Pure client-side — no hub involvement.
+Results link back to the group page. Accessible from sidebar.
+
+### Tests added
+
+- 8 tests: group self-service (create, join open, join invite rejected, join already member, members list, non-member denied, search, join triggers notification)
+- 3 tests: AES GEK wrap/unwrap (round-trip, wrong key rejected, differs from ChaCha20 wrap)
+
+---
+
 ## Phase 11 — Android client MVP
 
 **Objective:** Android app for account creation, group browsing, file download,