fix: ruff linting errors and add comprehensive test coverage for asset queries

- Fix unused imports in routes.py, asset.py, manager.py, asset_management.py, ingest.py
- Fix whitespace issues in upload.py, asset_info.py, ingest.py
- Fix typo in manager.py (stray character after result["asset"])
- Fix broken import in test_metadata.py (project_kv moved to asset_info.py)
- Add fixture override in queries/conftest.py for unit test isolation

Add 48 new tests covering all previously untested query functions:
- asset.py: upsert_asset, bulk_insert_assets
- cache_state.py: upsert_cache_state, delete_cache_states_outside_prefixes,
  get_orphaned_seed_asset_ids, delete_assets_by_ids, get_cache_states_for_prefixes,
  bulk_set_needs_verify, delete_cache_states_by_ids, delete_orphaned_seed_asset,
  bulk_insert_cache_states_ignore_conflicts, get_cache_states_by_paths_and_asset_ids
- asset_info.py: insert_asset_info, get_or_create_asset_info,
  update_asset_info_timestamps, replace_asset_info_metadata_projection,
  bulk_insert_asset_infos_ignore_conflicts, get_asset_info_ids_by_ids
- tags.py: bulk_insert_tags_and_meta

Total: 119 tests pass (up from 71)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/assets/api/routes.py

@@ -2,7 +2,6 @@ import logging
 import uuid
 import urllib.parse
 import os
-import contextlib
 from aiohttp import web
 
 from pydantic import ValidationError
@@ -20,7 +19,6 @@ from app.assets.api.upload import parse_multipart_upload
 from app.assets.services.scanner import seed_assets
 from typing import Any
 
-import folder_paths
 
 ROUTES = web.RouteTableDef()
 USER_MANAGER: user_manager.UserManager | None = None

app/assets/api/upload.py

@@ -16,7 +16,7 @@ from app.assets.api.schemas_in import ParsedUpload, UploadError
 def validate_hash_format(s: str) -> str:
     """
     Validate and normalize a hash string.
-    
+
     Returns canonical 'blake3:<hex>' or raises UploadError.
     """
     s = s.strip().lower()