Add contractor sharing feature and move settings to navigation bar

Contractor Sharing:
- Add .casera file format for sharing contractors between users
- Create SharedContractor model with JSON serialization
- Implement ContractorSharingManager for iOS (Swift) and Android (Kotlin)
- Register .casera file type in iOS Info.plist and Android manifest
- Add share button to ContractorDetailView (iOS) and ContractorDetailScreen (Android)
- Add import confirmation, success, and error dialogs
- Create expect/actual platform implementations for sharing and import handling

Navigation Changes:
- Remove Profile tab from bottom tab bar (iOS and Android)
- Add settings gear icon to left side of "My Properties" title
- Settings gear opens Profile/Settings screen as sheet (iOS) or navigates (Android)
- Add property button to top right action bar

Bug Fixes:
- Fix ResidenceUsersResponse to match API's flat array response format
- Fix GenerateShareCodeResponse handling to access nested shareCode property
- Update ManageUsersDialog to accept residenceOwnerId parameter

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

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

composeApp/src/androidMain/AndroidManifest.xml

@@ -39,6 +39,28 @@
                     android:scheme="casera"
                     android:host="reset-password" />
             </intent-filter>
+
+            <!-- .casera file import -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data android:scheme="content" />
+                <data android:scheme="file" />
+                <data android:host="*" />
+                <data android:mimeType="*/*" />
+                <data android:pathPattern=".*\\.casera" />
+            </intent-filter>
+
+            <!-- .casera file import via content:// -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+
+                <data android:scheme="content" />
+                <data android:mimeType="application/octet-stream" />
+            </intent-filter>
         </activity>
 
         <!-- FileProvider for camera photos -->