feat: Implement email sending utilities and templates for job notifications

- Added email_service.py for sending emails with SMTP configuration.
- Introduced email_templates.py to render job alert email subjects and bodies.
- Enhanced scraper.py to extract contact information from job listings.
- Updated settings.js to handle negative keyword input validation.
- Created email.html and email_templates.html for managing email subscriptions and templates in the admin interface.
- Modified base.html to include links for email alerts and templates.
- Expanded user settings.html to allow management of negative keywords.
- Updated utils.py to include functions for retrieving negative keywords and email settings.
- Enhanced job filtering logic to exclude jobs containing negative keywords.

tests/test_admin_email.py

@@ -0,0 +1,84 @@
+import pytest
+from sqlalchemy import text
+
+from web.app import app
+from web.db import (
+    db_init,
+    create_or_update_user,
+    subscribe_email,
+    list_email_subscriptions,
+    _ensure_session,
+)
+
+
+@pytest.fixture(scope="function", autouse=True)
+def initialize_app():
+    app.config.update(TESTING=True, WTF_CSRF_ENABLED=False)
+    with app.app_context():
+        db_init()
+        create_or_update_user("admin", password="secret",
+                              is_admin=True, is_active=True)
+    # Clear subscriptions before and after each test to avoid leakage
+    with _ensure_session() as session:
+        session.execute(text("DELETE FROM email_subscriptions"))
+        session.commit()
+    yield
+    with _ensure_session() as session:
+        session.execute(text("DELETE FROM email_subscriptions"))
+        session.commit()
+
+
+@pytest.fixture
+def client():
+    with app.test_client() as test_client:
+        with test_client.session_transaction() as sess:
+            sess["username"] = "admin"
+        yield test_client
+
+
+@pytest.fixture
+def anon_client():
+    with app.test_client() as test_client:
+        # Ensure no admin session present
+        with test_client.session_transaction() as sess:
+            sess.pop("username", None)
+        yield test_client
+
+
+def test_admin_emails_requires_admin(anon_client):
+    response = anon_client.get("/admin/emails")
+    assert response.status_code == 302
+    assert "/login" in response.headers.get("Location", "")
+
+
+def test_admin_emails_lists_subscriptions(client):
+    subscribe_email("alice@example.com")
+    response = client.get("/admin/emails")
+    assert response.status_code == 200
+    assert b"alice@example.com" in response.data
+
+
+def test_admin_emails_can_subscribe(client):
+    response = client.post(
+        "/admin/emails",
+        data={"action": "subscribe", "email": "bob@example.com"},
+        follow_redirects=False,
+    )
+    assert response.status_code == 302
+    emails = list_email_subscriptions()
+    assert any(sub["email"] == "bob@example.com" and sub["is_active"]
+               for sub in emails)
+
+
+def test_admin_emails_can_unsubscribe(client):
+    subscribe_email("carol@example.com")
+    response = client.post(
+        "/admin/emails",
+        data={"action": "unsubscribe", "email": "carol@example.com"},
+        follow_redirects=False,
+    )
+    assert response.status_code == 302
+    emails = list_email_subscriptions()
+    matching = [sub for sub in emails if sub["email"] == "carol@example.com"]
+    assert matching
+    assert matching[0]["is_active"] is False