feat: add comprehensive testing mechanism for dashboard features

- Add smoke test script for post-deployment verification
- Add health monitoring script with Telegram alerts
- Add backend integration tests for conversation tracker API
- Add frontend tests to verify correct API paths
- Update CI/CD workflows to enforce test failures and run smoke tests
- Add comprehensive testing documentation

This testing mechanism will catch issues like the double /api/ prefix bug
before they reach users.

dashboard/backend/tests/integration/test_conversation_tracker.py

@@ -0,0 +1,81 @@
+import pytest
+from fastapi.testclient import TestClient
+
+
+class TestConversationTrackerAPI:
+    """Test conversation tracker endpoints"""
+
+    def test_list_dates_requires_auth(self, test_app):
+        """Verify dates endpoint requires authentication"""
+        response = test_app.get("/api/conversations/dates")
+        assert response.status_code == 401
+        assert "Not authenticated" in response.json()["detail"]
+
+    def test_list_dates_with_auth(self, test_app, admin_headers, mock_conversation_db):
+        """Verify dates endpoint returns data with auth"""
+        response = test_app.get("/api/conversations/dates", headers=admin_headers)
+        assert response.status_code == 200
+        assert isinstance(response.json(), list)
+
+    def test_get_summary_not_found(self, test_app, admin_headers, mock_conversation_db):
+        """Test daily summary endpoint returns 404 when no summary exists"""
+        response = test_app.get("/api/conversations/summary/2026-04-19", headers=admin_headers)
+        assert response.status_code == 404
+
+    def test_list_conversations(self, test_app, admin_headers, mock_conversation_db):
+        """Test conversation list endpoint"""
+        response = test_app.get("/api/conversations/list?date=2026-04-19", headers=admin_headers)
+        assert response.status_code == 200
+        data = response.json()
+        assert isinstance(data, list)
+        if len(data) > 0:
+            assert "session_id" in data[0]
+            assert "project_path" in data[0]
+
+    def test_list_conversations_requires_auth(self, test_app):
+        """Test conversation list requires authentication"""
+        response = test_app.get("/api/conversations/list?date=2026-04-19")
+        assert response.status_code == 401
+
+    def test_get_conversation_detail(self, test_app, admin_headers, mock_conversation_db):
+        """Test conversation detail endpoint"""
+        response = test_app.get("/api/conversations/test-session-id", headers=admin_headers)
+        assert response.status_code in [200, 404]
+
+    def test_get_conversation_messages(self, test_app, admin_headers, mock_conversation_db):
+        """Test conversation messages endpoint"""
+        response = test_app.get("/api/conversations/test-session-id/messages", headers=admin_headers)
+        assert response.status_code in [200, 404]
+
+    def test_search_conversations(self, test_app, admin_headers, mock_conversation_db):
+        """Test search endpoint"""
+        response = test_app.get("/api/conversations/search?q=test", headers=admin_headers)
+        assert response.status_code == 200
+        assert isinstance(response.json(), list)
+
+    def test_search_requires_query(self, test_app, admin_headers, mock_conversation_db):
+        """Test search requires query parameter"""
+        response = test_app.get("/api/conversations/search", headers=admin_headers)
+        # Should handle missing query gracefully
+        assert response.status_code in [200, 400, 422]
+
+    def test_get_stats(self, test_app, admin_headers, mock_conversation_db):
+        """Test stats endpoint"""
+        response = test_app.get("/api/conversations/stats", headers=admin_headers)
+        assert response.status_code == 200
+        data = response.json()
+        assert "top_projects" in data
+        assert "top_tools" in data
+        assert isinstance(data["top_projects"], list)
+        assert isinstance(data["top_tools"], list)
+
+    def test_trigger_summary_requires_auth(self, test_app):
+        """Test trigger endpoint requires authentication"""
+        response = test_app.post("/api/conversations/trigger")
+        assert response.status_code == 401
+
+    def test_api_prefix_correct(self, test_app, admin_headers):
+        """Test that API paths don't have double /api/ prefix"""
+        # This should be 404, not a valid endpoint
+        response = test_app.get("/api/api/conversations/dates", headers=admin_headers)
+        assert response.status_code == 404