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>

iosApp/iosApp/Helpers/AccessibilityIdentifiers.swift

@@ -36,6 +36,7 @@ struct AccessibilityIdentifiers {
         static let documentsTab = "TabBar.Documents"
         static let profileTab = "TabBar.Profile"
         static let backButton = "Navigation.BackButton"
+        static let settingsButton = "Navigation.SettingsButton"
     }
 
     // MARK: - Residence

iosApp/iosApp/Helpers/L10n.swift

@@ -582,6 +582,8 @@ enum L10n {
         static var yes: String { String(localized: "common_yes") }
         static var no: String { String(localized: "common_no") }
         static var ok: String { String(localized: "common_ok") }
+        static var share: String { String(localized: "common_share") }
+        static var `import`: String { String(localized: "common_import") }
     }
 
     // MARK: - Errors