Fix contact backup export: contactMethods now exports as JSON arrays instead of strings

- Fixed contactsToExportJson to export contactMethods as proper arrays instead of stringified JSON
- Added JSON parsing for contactMethods in _mapColumnsToValues when retrieving from database
- Updated $insertContact to properly handle contactMethods field storage
- Removed unused ContactWithJsonStrings import
ref:  https://app.clickup.com/t/86b63ffpb
Resolves issue where contact backup exports showed contactMethods as "[]" strings instead of proper JSON arrays.

src/utils/PlatformServiceMixin.ts

@@ -246,6 +246,15 @@ export const PlatformServiceMixin = {
             // Keep null values as null
           }
 
+          // Handle JSON fields like contactMethods
+          if (column === "contactMethods" && typeof value === "string") {
+            try {
+              value = JSON.parse(value);
+            } catch {
+              value = [];
+            }
+          }
+
           obj[column] = value;
         });
         return obj;
@@ -1051,12 +1060,18 @@ export const PlatformServiceMixin = {
             contact.profileImageUrl !== undefined
               ? contact.profileImageUrl
               : null,
+          contactMethods:
+            contact.contactMethods !== undefined
+              ? (Array.isArray(contact.contactMethods)
+                  ? JSON.stringify(contact.contactMethods)
+                  : contact.contactMethods)
+              : null,
         };
 
         await this.$dbExec(
           `INSERT OR REPLACE INTO contacts 
-           (did, name, publicKeyBase64, seesMe, registered, nextPubKeyHashB64, profileImageUrl) 
-           VALUES (?, ?, ?, ?, ?, ?, ?)`,
+           (did, name, publicKeyBase64, seesMe, registered, nextPubKeyHashB64, profileImageUrl, contactMethods) 
+           VALUES (?, ?, ?, ?, ?, ?, ?, ?)`,
           [
             safeContact.did,
             safeContact.name,
@@ -1065,6 +1080,7 @@ export const PlatformServiceMixin = {
             safeContact.registered,
             safeContact.nextPubKeyHashB64,
             safeContact.profileImageUrl,
+            safeContact.contactMethods,
           ],
         );
         return true;