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/integration/test_bike_matching_job.py

@@ -0,0 +1,39 @@
+
+import pytest
+from unittest.mock import MagicMock, patch
+from src.services.bike_matching import run_matching_for_all
+from src.models.activity import Activity
+from src.models.bike_setup import BikeSetup
+
+def test_bike_matching_job_updates_progress():
+    """
+    Verify that run_matching_for_all calls job_manager.update_job
+    when a job_id is provided.
+    """
+    mock_db = MagicMock()
+    
+    # Mock Activities
+    activities = [
+        Activity(id=1, activity_type="cycling", bike_setup_id=None, bike_match_confidence=None),
+        Activity(id=2, activity_type="cycling", bike_setup_id=None, bike_match_confidence=None)
+    ]
+    
+    # Setup Query chain
+    mock_db.query.return_value.filter.return_value.all.return_value = activities
+    
+    with patch("src.services.bike_matching.process_activity_matching") as mock_process:
+        with patch("src.services.job_manager.job_manager") as mock_job_manager:
+            # Important: Ensure expecting cancellation returns False, otherwise loop breaks
+            mock_job_manager.should_cancel.return_value = False
+            
+            run_matching_for_all(mock_db, job_id="test-job-123")
+            
+            # Verify update_job called at start
+            mock_job_manager.update_job.assert_any_call("test-job-123", message="Found 2 candidates. Matching...", progress=0)
+            
+            # Verify update_job called during loop (progress)
+            # 2 items, index 0 satisfies % 10 == 0
+            mock_job_manager.update_job.assert_any_call("test-job-123", progress=0)
+            
+            # Verify process was called
+            assert mock_process.call_count == 2