Address PR #852 round 2:
- config: DOCUMENT_PDF_GRAPHICS_LIMIT validator is now gte=1 (pymupdf4llm treats
0 as "no cap", which would re-expose the OOM); documented the zero semantics
and that the per-worker mem rlimit needs a pod restart to change.
- processor: annotate `_index_document -> bool | None` and document the contract
so the `if indexed is False` check is explicit/type-checkable.
- tests: add the RLIM_INFINITY-hard branch assertion for _apply_mem_limit
(soft==target, hard stays unbounded).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>