Merge branch 'main' into anydoc-support

Conflicts, and how each was taken:

- application/core/settings.py — ours. The renamed OCR_ENABLED /
  OCR_ATTACHMENTS_ENABLED / OCR_MIN_CHARS_PER_PAGE accept main's
  DOCLING_OCR_* spellings as AliasChoices, so nothing is dropped.
- application/Dockerfile — both. Main's install layers plus the
  INSTALL_DOCLING build arg.
- application/parser/file/constants.py — both imports.
- deployment/docker-compose.yaml — both. The INSTALL_DOCLING /
  INSTALL_TESSERACT build args on backend and worker, and main's
  -Q docsgpt,parsing,embeddings, which query embedding needs.
- tests/conftest.py — theirs. Both sides fixed the same pytest-postgresql
  9.0.0 autocommit= breakage; main's spelling is the one already on main.
- application/requirements.txt — the comments claimed different reasons
  torch is in core. Main's is the true one now: it removed
  sentence-transformers, so docling is torch's only remaining consumer.

Two things the merge broke without conflicting:

- onnxruntime. This branch moved it out of core into the docling extra;
  main meanwhile made it the runtime local embeddings execute on
  (fastembed). Git took the deletion, leaving fastembed with no pinned
  runtime in a repo that pins everything. Restored to core, and no longer
  pinned twice from the extra.
- The frontend copy of ATTACHMENT_PARSER_EXTENSIONS. The backend list is
  derived and picked up the anydoc suffixes; the hand-kept frontend mirror
  did not, so the composer would refuse files the API accepts.
  tests/parser/file/test_constants.py is what caught it.

ruff, pytest (9897 passed), frontend build and docs build all pass. The
image build is unverified: no Docker daemon on this machine.

deployment/sandbox/README.md

@@ -214,7 +214,7 @@ and leaves this worker light.
 worker must also consume `parsing`, or the tool's await never resolves:
 
 ```bash
-celery -A application.app.celery worker -Q docsgpt,parsing -l INFO
+celery -A application.app.celery worker -Q docsgpt,parsing,embeddings -l INFO
 ```
 
 Tuning settings: `DOCUMENT_PARSE_TIMEOUT` (seconds the tool awaits before