Complete Firebase setup with Data Connect and security rules

- Initialize Firebase Data Connect
- Deploy Firestore security rules for SMTP config
- Update firebase.json with Firestore configuration
- Add generated Data Connect SDKs

.firebaserc

@@ -0,0 +1,5 @@
+{
+  "projects": {
+    "default": "prayer-app-6701f"
+  }
+}