Fix worker-only database architecture and Vue Proxy serialization

- Implement worker-only database access to eliminate double migrations
- Add parameter serialization in usePlatformService to prevent Capacitor "object could not be cloned" errors
- Fix infinite logging loop with circuit breaker in databaseUtil
- Use dynamic imports in WebPlatformService to prevent worker thread errors
- Add higher-level database methods (getContacts, getSettings) to composable
- Eliminate Vue Proxy objects through JSON serialization and Object.freeze protection

Resolves Proxy(Array) serialization failures and worker context conflicts across Web/Capacitor/Electron platforms.

docker/nginx.conf

@@ -63,6 +63,10 @@ http {
     add_header Referrer-Policy "strict-origin-when-cross-origin" always;
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self' data:; connect-src 'self' https:; frame-ancestors 'self';" always;
 
+    # SharedArrayBuffer support headers for absurd-sql
+    add_header Cross-Origin-Opener-Policy "same-origin" always;
+    add_header Cross-Origin-Embedder-Policy "require-corp" always;
+
     # Rate limiting
     limit_req_zone $binary_remote_addr zone=api:10m rate=10r/s;
     limit_req_zone $binary_remote_addr zone=login:10m rate=1r/s;