feat: implement Fitbit OAuth, Garmin MFA, and optimize segment discovery

- Add Fitbit authentication flow (save credentials, OAuth callback handling)
- Implement Garmin MFA support with successful session/cookie handling
- Optimize segment discovery with new sampling and activity query services
- Refactor database session management in discovery API for better testability
- Enhance activity data parsing for charts and analysis
- Update tests to use testcontainers and proper dependency injection
- Clean up repository by ignoring and removing tracked transient files (.pyc, .db)

FitnessSync/backend/tests/conftest.py

@@ -2,13 +2,16 @@ import sys
 import os
 import pytest
 from starlette.testclient import TestClient
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, text
 from sqlalchemy.orm import sessionmaker
+from testcontainers.postgres import PostgresContainer
+import time
 
-sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__)))) # Add backend root
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__)))) # Add backend root to START of path
+os.environ["TESTING"] = "1"
 
 from main import app
-from src.models.base import Base # Explicitly import Base from its definition
+from src.models.base import Base 
 # Import all models to ensure Base.metadata.create_all is aware of them
 from src.models.api_token import APIToken
 from src.models.activity import Activity
@@ -16,40 +19,62 @@ from src.models.auth_status import AuthStatus
 from src.models.config import Configuration
 from src.models.health_metric import HealthMetric
 from src.models.sync_log import SyncLog
-from src.models.weight_record import WeightRecord # Ensure all models are imported
-from src.api.status import get_db # Import get_db from an API file
-import os
-
-# Use an in-memory SQLite database for testing
-SQLALCHEMY_DATABASE_URL = "sqlite:///./test.db"
-
-engine = create_engine(
-    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
-)
-TestingSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
-
+from src.models.weight_record import WeightRecord
+from src.models.stream import ActivityStream 
+from src.api.status import get_db
 
 @pytest.fixture(scope="session")
-def db_engine():
-    """Create a test database engine."""
-    Base.metadata.create_all(bind=engine)  # Create tables
+def postgres_container():
+    """Spin up a Postgres container with PostGIS."""
+    print("DEBUG: Starting Postgres Container...")
+    # Use postgis/postgis image
+    postgres = PostgresContainer("postgis/postgis:15-3.4")
+    postgres.start()
+    print("DEBUG: Postgres Container Started.")
+    try:
+        yield postgres
+    finally:
+        postgres.stop()
+
+@pytest.fixture(scope="session")
+def db_engine(postgres_container):
+    """Create a test database engine connected to the container."""
+    print("DEBUG: Configuring DB Engine...")
+    # Ensure usage of psycopg2 driver
+    db_url = postgres_container.get_connection_url().replace("postgresql://", "postgresql+psycopg2://")
+    
+    engine = create_engine(db_url)
+    
+    # Enable PostGIS extension
+    with engine.connect() as conn:
+        conn.execute(text("CREATE EXTENSION IF NOT EXISTS postgis"))
+        conn.commit()
+    
+    # Create tables
+    Base.metadata.create_all(bind=engine)
+    
     yield engine
-    Base.metadata.drop_all(bind=engine)  # Drop tables after tests
+    
+    # Teardown logic
+    Base.metadata.drop_all(bind=engine)
 
 
-@pytest.fixture(scope="module")
+@pytest.fixture(scope="function")
 def db_session(db_engine):
     """Create a test database session."""
+    TestingSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=db_engine)
     connection = db_engine.connect()
     transaction = connection.begin()
     session = TestingSessionLocal(bind=connection)
+    
     yield session
+    
     session.close()
     transaction.rollback()
     connection.close()
 
 
-@pytest.fixture(scope="module")
+@pytest.fixture(scope="function")
 def client(db_session):
     """Create a FastAPI test client."""
 
@@ -57,7 +82,7 @@ def client(db_session):
         try:
             yield db_session
         finally:
-            db_session.close()
+            pass
 
     app.dependency_overrides[get_db] = override_get_db
     with TestClient(app) as c: