MED-01 - move remaining blocking work off the event loop:
- normalization.py gains normalize_orientation_async; the Pillow decode,
transpose, and re-encode now run via asyncio.to_thread. The sync entry point
stays for tests and documents that it blocks.
- OrientationNormalization.digest_sha256 becomes a stored field computed inside
normalize_orientation, which already runs off-loop, instead of a property that
hashed page-sized derivative bytes on the caller's thread.
- SourceService._write_and_digest_artifact performs the artifact write and its
sha256 in a single worker-thread hop; both external-artifact write sites are
now dispatched through to_thread.
- transcribe_image dispatches load_source_payload and build_prompt_execution
through to_thread.
MED-04 - replace functools.cache on the engine and session factories with
explicit URL-keyed registries. dispose_engine and dispose_session_factory now
evict only the requested URL; previously cache_clear() tore down every other
database in the process, and dispose_engine would construct an engine for an
unknown URL purely to throw it away. New tests/test_engine_registry.py covers
distinct engines per URL, targeted eviction, and the unknown-URL no-op.
config.py - replace object.__setattr__ in normalize_provider_models with a
model_validator(mode="before") over the raw input, so the derived selector is
produced by normal construction rather than by mutating a frozen instance.
model_copy(update=...) was tried first and rejected: pydantic-settings does not
support a top-level validator returning anything other than self when validating
via __init__. provider_model is now stripped as well as the tuple entries.
models.py - add onupdate to the five updated_at columns and to Job.date_updated,
and drop the 10 manual "updated_at = datetime.now(UTC)" assignments across the
document, job, people, registry, and source services. Verified DDL-neutral by
hashing CreateTable output for every table on both the sqlite and postgresql
dialects before and after: identical, so this stays in Phase 6 and Phase 2 does
not need re-verification. New tests/services/test_timestamps.py asserts an
update through each service advances the timestamp.
MED-08 - Job.filename no longer swallows every exception to None. Relationships
declare lazy="raise", so the new _loaded_attribute helper inspects load state
explicitly and returns None only for genuinely unloaded attributes; real errors
now surface. Job.error_detail uses the same helper, which also removes its
unguarded read of the lazy="raise" job_sources relationship.
Verification: ruff check src tests clean; 288 passed, 4 skipped.
Co-authored-by: Copilot App <[email protected]>
