Remove E2EE and switch to plaintext messaging

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CLAUDE.md

@@ -179,40 +179,3 @@ backgroundColor: 'rgba(18, 18, 18, 0.85)',
 The `BlurView` in `tabBarBackground` is unreliable and can fail during re-renders/transitions, causing a fully transparent tab bar. The solid rgba background acts as a fallback while still allowing the blur effect on top.
 
 **Location:** `apps/mobile/app/(app)/_layout.tsx` - `tabBarStyle`
-
-## E2EE (End-to-End Encryption) Implementation
-
-Chat messages (text, images, videos) are encrypted client-side using AES-256-GCM with triple-wrapped RSA keys.
-
-### Architecture
-- **Full documentation:** See `docs/e2ee-implementation.md` for complete details
-- **Encryption library:** `apps/mobile/src/lib/encryption/`
-- **React hooks:** `apps/mobile/src/hooks/useEncryptionKeys.ts`, `useDecryptedMessage.ts`
-- **Edge functions:** `handle-key-rotation`, `reencrypt-pending-messages`
-
-### Key Concepts
-1. **Message versions:** v1 = plaintext (legacy), v2 = E2EE
-2. **Triple-wrapped keys:** Each message's AES key is RSA-encrypted for sender, recipient, and admin
-3. **Device recovery:** When user gets new device, admin key re-wraps messages for new user key
-
-### Database Tables
-- `messages.version` - Encryption version (1 or 2)
-- `messages.encrypted_content` - Base64 ciphertext
-- `messages.encryption_iv` - Base64 IV for AES-GCM
-- `messages.keys_metadata` - JSONB with wrapped keys
-- `profiles.public_key_jwk` - User's RSA public key
-- `master_keys` - Admin RSA public keys
-
-### Setup Required
-1. Run `node scripts/generate-admin-keys.mjs` to generate admin keypair
-2. Insert public key into `master_keys` table
-3. Store private key in `ADMIN_PRIVATE_KEY_JWK` environment variable for edge functions
-4. Install crypto dependency: `npm install react-native-quick-crypto@^0.7.x`
-5. Run `npx expo prebuild --clean` after installation
-
-### Edge Functions for E2EE
-| Function | verify_jwt | Purpose |
-|----------|------------|---------|
-| `handle-key-rotation` | false | Re-wraps message keys when user gets new device |
-| `reencrypt-pending-messages` | false | Wraps keys for recipient after they generate keys |
-