refactor: move in-function imports to top-level and remove keyword-only argument pattern

- Move imports from inside functions to module top-level in:
  - app/assets/database/queries/asset.py
  - app/assets/database/queries/asset_info.py
  - app/assets/database/queries/cache_state.py
  - app/assets/manager.py
  - app/assets/services/asset_management.py
  - app/assets/services/ingest.py

- Remove keyword-only argument markers (*,) from app/assets/ to match codebase conventions

Amp-Thread-ID: https://ampcode.com/threads/T-019c24eb-bfa2-727f-8212-8bc976048604
Co-authored-by: Amp <amp@ampcode.com>

app/assets/database/bulk_ops.py

@@ -27,7 +27,6 @@ def _rows_per_stmt(cols: int) -> int:
 
 def seed_from_paths_batch(
     session: Session,
-    *,
     specs: list[dict],
     owner_id: str = "",
 ) -> dict:
@@ -177,7 +176,6 @@ def seed_from_paths_batch(
 
 def bulk_insert_tags_and_meta(
     session: Session,
-    *,
     tag_rows: list[dict],
     meta_rows: list[dict],
     max_bind_params: int,