Update icons, screenshots, and UX improvements

- Refactor icon picker to use full Ionicons set dynamically
- Add date sort toggle to My Answers screen
- Fix match deduplication and show total count on home
- Clear stale data when switching chats
- Update app store screenshots
- Bump build number to 25

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/mobile/app.json

@@ -16,7 +16,7 @@
     "ios": {
       "supportsTablet": false,
       "bundleIdentifier": "com.sauci.app",
-      "buildNumber": "24",
+      "buildNumber": "25",
       "usesAppleSignIn": true,
       "infoPlist": {
         "UIBackgroundModes": [