Implements mobile Nostr identity management per issue #29.
Android — NIP-55 Amber integration:
- Opens com.greenart7c3.nostrsigner via `nostrsigner:` URI scheme to
retrieve the user's public key without exposing it to the app.
- Listens for the `mobile://nostr-callback` deep link response and stores
the resulting npub in Expo SecureStore.
- Falls back to Play Store install prompt when Amber is not installed.
iOS / manual fallback:
- NostrConnectModal accepts an nsec1 paste-in, validates bech32, derives
the pubkey via nostr-tools getPublicKey, and stores the key only in
Expo SecureStore — never in AsyncStorage, Redux, or logs.
Both platforms:
- Truncated npub and signer type (Amber / nsec) shown in Settings.
- "Disconnect Nostr" wipes all keys from SecureStore and resets state.
- Identity persists across restarts via SecureStore.
Supporting changes:
- NostrContext: new React context for identity lifecycle.
- NostrConnectModal: platform-aware bottom-sheet modal for connect flow.
- TimmyContext: added apiBaseUrl/setApiBaseUrl/isConnected; URL persisted
in AsyncStorage and restored on mount; circular dep broken via refs.
- constants/colors: added field, textInverted, destructive, link colours.
- constants/storage-keys: added SERVER_URL_KEY.
- app.json: added Android intent filter for mobile://nostr-callback.
- package.json: added nostr-tools and expo-secure-store dependencies.
Fixes#29
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
## Original task
Validate and fix the Expo mobile app (Face/Matrix/Feed tabs) against the live API server.
Restart the API server (was EADDRINUSE from prior merge), verify domain config, test all three tabs, fix issues, and confirm TypeScript typecheck passes.
## Changes made
### artifacts/mobile/app/(tabs)/matrix.tsx
- Fixed getMatrixUrl(): was returning `https://{domain}/` (API landing page), now returns `https://{domain}/tower` (Three.js 3D world). This was the main UI bug — the Matrix tab was showing the wrong page.
### artifacts/api-server/src/app.ts
- Fixed tower static file path: replaced `path.resolve(process.cwd(), "the-matrix", "dist")` with `path.resolve(__dirname_app, "../../..", "the-matrix", "dist")` using `fileURLToPath(import.meta.url)`.
- Root cause: pnpm `--filter` runs scripts from the package directory (`artifacts/api-server`), so `process.cwd()` resolved to `artifacts/api-server/the-matrix/dist` (missing), not `the-matrix/dist` at workspace root. This caused /tower to 404 in development.
- The import.meta.url approach works correctly in both dev (tsx from src/) and production (esbuild CJS bundle from dist/) since both are 3 levels deep from workspace root.
### Infrastructure
- Killed stale process on port 18115, restarted Expo workflow (was stuck waiting for port with interactive prompt).
- Restarted API server (was EADDRINUSE from prior task merge).
## Verification
- API healthz returns 200, /tower/ returns 200.
- TypeScript typecheck passes for @workspace/mobile (no errors).
- TypeScript typecheck passes for @workspace/api-server (no errors).
- Expo dev server running on port 18115, Metro bundler active.
- WebSocket connections visible in API server logs (clients connected).
- EXPO_PUBLIC_DOMAIN set to $REPLIT_DEV_DOMAIN in dev script (correct for wss:// and https:// connections).
