feat(mobile): Add semantic versioning with standard-version

- Add standard-version for automated version bumping
- Create .versionrc with custom configuration for app.json
- Add version-updater.cjs script for Expo version syncing
- Add version bump scripts (release, release:patch, release:minor, release:major)
- Initialize CHANGELOG.md with v1.0.0 release notes
- Add iOS buildNumber and Android versionCode for app store releases
- Update .gitignore to allow CHANGELOG.md

This establishes proper engineering practices for version management.

mobile/app.json

@@ -14,12 +14,15 @@
     },
     "ios": {
       "supportsTablet": true,
+      "bundleIdentifier": "io.pezkuwichain.wallet",
+      "buildNumber": "10000",
       "infoPlist": {
         "NSCameraUsageDescription": "Pezkuwi needs camera access to scan QR codes for wallet addresses and payments."
       }
     },
     "android": {
       "package": "io.pezkuwichain.wallet",
+      "versionCode": 10000,
       "adaptiveIcon": {
         "foregroundImage": "./assets/adaptive-icon.png",
         "backgroundColor": "#ffffff"