fix: resolve cross-platform contactMethods JSON parsing inconsistencies

- Add platform-agnostic parseJsonField utility for contactMethods handling
- Update contact export functions (contactsToExportJson, contactToCsvLine)
- Fix contact storage in QR scan views (ContactQRScanShowView, ContactQRScanFullView)
- Ensure consistent JSON string storage across web SQLite and Capacitor SQLite
- Prevents "[object Object] is not valid JSON" errors when switching platforms
- Maintains compatibility between auto-parsing web SQLite and raw string Capacitor SQLite

Fixes: contactMethods parsing errors in export and QR scan functionality
Related: searchBoxes field had similar issue (already fixed)

src/views/ContactQRScanFullView.vue

@@ -124,6 +124,7 @@ import UserNameDialog from "../components/UserNameDialog.vue";
 import { generateEndorserJwtUrlForAccount } from "../libs/endorserServer";
 import { retrieveAccountMetadata } from "../libs/util";
 import { PlatformServiceFactory } from "@/services/PlatformServiceFactory";
+import { parseJsonField } from "../db/databaseUtil";
 
 interface QRScanResult {
   rawValue?: string;
@@ -474,7 +475,7 @@ export default class ContactQRScan extends Vue {
 
       // Add new contact
       // @ts-expect-error because we're just using the value to store to the DB
-      contact.contactMethods = JSON.stringify(contact.contactMethods);
+      contact.contactMethods = JSON.stringify(parseJsonField(contact.contactMethods, []));
       const { sql, params } = databaseUtil.generateInsertStatement(
         contact as unknown as Record<string, unknown>,
         "contacts",