Add push notification functionality with tests and digest scheduler

- Implemented push subscription API with tests for subscribing and unsubscribing users.
- Created web push notification tests triggered by child actions.
- Added digest scheduler to send email digests to users at 9 PM local time.
- Developed utility functions for creating and validating digest action tokens.
- Integrated web push sender to handle sending notifications to users.
- Added service worker for handling push notifications in the frontend.
- Created a push opt-in component for user notification preferences.
- Implemented tests for the push opt-in component to ensure correct behavior.
- Updated frontend services to manage push subscriptions and permissions.

backend/utils/email_sender.py

@@ -60,4 +60,83 @@ def send_pin_setup_email(to_email: str, code: str) -> None:
         Mail(current_app).send(msg)
         print(f"[EMAIL to {to_email}] Parent PIN setup code: {code}")
     except Exception:
-        print(f"Failed to send email to {to_email}. Parent PIN setup code: {code}")
+        print(f"Failed to send email to {to_email}. Parent PIN setup code: {code}")
+
+
+def send_digest_email(to_email: str, items: list, unsubscribe_token: str) -> None:
+    """
+    Send the nightly digest email listing pending chore/reward items.
+
+    Each item in `items` is a dict with keys:
+        child_name, entity_name, entity_type, view_url, approve_url, deny_url
+    Items are grouped by child_name in the email.
+    """
+    frontend_url = current_app.config.get('FRONTEND_URL', 'https://localhost:5173')
+    unsubscribe_url = f"{frontend_url}/api/digest-unsubscribe/{unsubscribe_token}"
+
+    # Group items by child
+    from collections import defaultdict
+    by_child: dict = defaultdict(list)
+    for item in items:
+        by_child[item['child_name']].append(item)
+
+    child_sections = ''
+    for child_name, child_items in by_child.items():
+        rows = ''
+        for item in child_items:
+            entity_label = 'Chore' if item['entity_type'] == 'chore' else 'Reward'
+            rows += f"""
+            <tr>
+              <td style="padding:8px 4px;border-bottom:1px solid #eee;">
+                <span style="font-weight:500;">{item['entity_name']}</span>
+                <span style="color:#888;font-size:0.85em;margin-left:6px;">{entity_label}</span>
+              </td>
+              <td style="padding:8px 4px;border-bottom:1px solid #eee;text-align:center;">
+                <a href="{item['view_url']}"
+                   style="color:#0066cc;text-decoration:underline;margin-right:8px;">View</a>
+                <a href="{item['approve_url']}"
+                   style="color:#22863a;font-weight:bold;text-decoration:underline;margin-right:8px;">Approve</a>
+                <a href="{item['deny_url']}"
+                   style="color:#cb2431;font-weight:bold;text-decoration:underline;">Deny</a>
+              </td>
+            </tr>"""
+
+        child_sections += f"""
+        <div style="margin-bottom:24px;">
+          <h3 style="color:#333;margin:0 0 8px 0;font-size:1rem;">{child_name}</h3>
+          <table style="width:100%;border-collapse:collapse;font-size:0.92rem;">
+            <tbody>{rows}</tbody>
+          </table>
+        </div>"""
+
+    html_body = f"""
+    <div style="font-family:sans-serif;max-width:600px;margin:0 auto;">
+      <div style="background:#4a90e2;color:#fff;padding:18px 24px;border-radius:6px 6px 0 0;">
+        <h2 style="margin:0;font-size:1.2rem;">Reward App &mdash; Daily Summary</h2>
+      </div>
+      <div style="background:#fff;padding:24px;border:1px solid #ddd;border-top:none;border-radius:0 0 6px 6px;">
+        <p style="color:#555;margin:0 0 20px 0;">
+          You have pending items that need your attention:
+        </p>
+        {child_sections}
+      </div>
+      <div style="color:#aaa;font-size:0.8rem;padding:12px 0;text-align:center;">
+        Reward App &bull;
+        <a href="{unsubscribe_url}" style="color:#aaa;">Unsubscribe from daily digest</a>
+      </div>
+    </div>
+    """
+
+    msg = Message(
+        subject='Reward App — Daily Summary',
+        recipients=[to_email],
+        html=html_body,
+        sender=current_app.config.get('MAIL_DEFAULT_SENDER', 'no-reply@reward-app.local'),
+    )
+    try:
+        if os.environ.get('DB_ENV') == 'e2e':
+            return
+        Mail(current_app).send(msg)
+        print(f"[EMAIL to {to_email}] Daily digest sent ({len(items)} items)")
+    except Exception:
+        print(f"Failed to send digest email to {to_email}")