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/conftest.py

@@ -287,3 +287,64 @@ def mock_request():
     request.client.host = "192.168.31.100"
     request.headers = {}
     return request
+
+
+@pytest.fixture
+def mock_conversation_db(tmp_path, monkeypatch):
+    """Mock conversation tracker database"""
+    import sqlite3
+
+    db_path = tmp_path / "conversations.db"
+
+    # Create minimal SQLite schema
+    conn = sqlite3.connect(db_path)
+    conn.execute("""
+        CREATE TABLE conversations (
+            session_id TEXT PRIMARY KEY,
+            project_path TEXT,
+            started_at DATETIME,
+            message_count INTEGER,
+            total_input_tokens INTEGER DEFAULT 0,
+            total_output_tokens INTEGER DEFAULT 0
+        )
+    """)
+    conn.execute("""
+        CREATE TABLE messages (
+            id INTEGER PRIMARY KEY AUTOINCREMENT,
+            session_id TEXT NOT NULL,
+            message_uuid TEXT UNIQUE NOT NULL,
+            role TEXT NOT NULL,
+            content_text TEXT,
+            timestamp DATETIME NOT NULL
+        )
+    """)
+    conn.execute("""
+        CREATE TABLE tool_calls (
+            id INTEGER PRIMARY KEY AUTOINCREMENT,
+            message_uuid TEXT NOT NULL,
+            tool_name TEXT NOT NULL,
+            timestamp DATETIME NOT NULL
+        )
+    """)
+    conn.execute("""
+        CREATE TABLE daily_summaries (
+            id INTEGER PRIMARY KEY AUTOINCREMENT,
+            date TEXT UNIQUE NOT NULL,
+            summary_content TEXT NOT NULL
+        )
+    """)
+
+    # Insert test data
+    conn.execute("""
+        INSERT INTO conversations VALUES
+        ('test-session-id', '/test/project', '2026-04-19 10:00:00', 10, 1000, 500)
+    """)
+    conn.execute("""
+        INSERT INTO messages VALUES
+        (1, 'test-session-id', 'msg-1', 'user', 'test message', '2026-04-19 10:00:00')
+    """)
+    conn.commit()
+    conn.close()
+
+    monkeypatch.setenv("CONVERSATION_TRACKER_DB", str(db_path))
+    return db_path