Squash-merge lib-standardisation: adopt repo standards across packaging,
tooling, docs, and CI.
- standardize pyproject.toml (canonical packaging, lint config, extras, GSDFC pydoclint)
- add py.typed marker, modernize type hints and Google-style docstrings
- nest generated docs under docs/lib and docs/mcp; add hand-written wiki
- adopt standard Type A PyPI CI pipeline (tag==version guard + quality gate)
- promote generated CHANGELOG.md; bump version to 0.0.3
- Replace deep imports with top-level omniread exports in tests
- Ensure tests validate only the supported public API surface
- Align HTML and PDF tests with documented library usage
- Introduce PDF submodule with client, scraper, and generic parser
- Add filesystem PDF client and test-only mock routing
- Add end-to-end PDF scrape → parse tests with typed output
- Mirror HTML module architecture for consistency
- Expose PDF primitives via omniread public API
