feat(ml): add database schema, config parser, and DVC setup

- Initialize DVC with local storage backend (task 1.6)
- Create PostgreSQL schema for training_runs table (task 1.7)
- Add SQLAlchemy database connection setup (task 1.8)
- Create Pydantic config models for pipeline.yaml (task 2.1)
- Add migration runner for database setup
- Fix pyproject.toml package discovery config

services/ml/.dvc/config

@@ -0,0 +1,5 @@
+[core]
+    no_scm = True
+    remote = local
+['remote "local"']
+    url = /home/homoludens/projekti/bitcon/candle_annotator/services/ml/dvc_storage