Migrate batch strategy enum to lookup table

[maxachis]

Summary

• migrate batches.strategy from Postgres enum storage to a batch_strategies lookup table with FK batches.batch_strategy_id
• add BatchStrategy ORM model and refactor batch write/read paths to resolve strategy names via lookup IDs
• update metrics/task queries to join through strategy lookup values while preserving API behavior
• add compatibility for existing tests/usages via Batch.strategy property and preserve lookup rows during test DB wipes
• add ruff as a dev dependency and run lint checks on touched files

Testing

• UV_CACHE_DIR=.uv-cache uv run ruff check (touched files)
• UV_CACHE_DIR=.uv-cache uv run pytest -q tests/automated/integration/api/metrics/batches tests/automated/integration/api/test_manual_batch.py tests/automated/integration/api/submit/data_source/test_core.py tests/automated/integration/db/client/test_insert_urls.py