release: v1.6.1 - bug-report filtering, DocFX API reference, Pages deploy - #3

The out-parameter overloads combined <inheritdoc cref=...> with explicit
<param> tags for parameters the inherited comment already documents, so
DocFX reported 14 "Duplicate parameter" warnings while generating metadata.

Keep <inheritdoc> for the parameters that are identical and document only
the extra out parameters (chdVersion/chdSha1/chdMd5). ReadHeader(Stream,...)
had no inherited parameters in common, so it now documents itself fully.

docfx metadata: 0 warnings.

The guides had a hand-written API page but no per-member reference.

- DocFX 2.81.0 is pinned in .config/dotnet-tools.json; docfx.json generates
  the managed reference for CHDSharpLib (net10.0) into docfx/ and renders the
  site to _site/api.
- scripts/build-api-docs.ps1 runs metadata + build + the theme step, so local
  and CI output are identical.
- .github/workflows/pages.yml builds the Jekyll guides and the API reference
  into one artifact and deploys it with actions/deploy-pages. GitHub Pages
  moves to build_type: workflow, so the wiki job no longer requests a legacy
  rebuild (ci.yml, release.yml).
- The CI docs job now also builds DocFX, so broken XML docs fail the gate.
- docs/_config.yml pins baseurl: /CHDSharp: Jekyll is no longer run by the
  Pages builder, which used to inject the project prefix.
- The sidebar and the hand-written API page link to /api/, and the reference
  uses the same GitHub-dark palette as the guides.
- Generated metadata (docfx/*.yml) and the rendered _site/ are git-ignored.

Bug-fix and documentation release.

- Expected user/usage errors no longer reach the Bug Report API (v1.6.0
  behavior change is already in main's fix commit).
- DocFX API reference published with the docs site.
- Version 1.6.1 in Directory.Build.props; WhatsNew.md, docs/ReleaseNotes.md,
  README.md, CHDSharpLib/README.md, per-project banners and
  PackageReleaseNotes updated; docs/building.md version examples refreshed.

…rloads

Replacing the duplicate <param> tags with <inheritdoc cref=...> removed the
DocFX warnings but introduced CS1573: Roslyn does not expand inheritdoc when
deciding whether a partially documented method is complete, and CHDSharpLib
turns that warning into an error for pack/build with -warnaserror.

Drop <inheritdoc> on the three out-parameter overloads and document every
parameter (and a summary) explicitly, so both DocFX and the compiler are
clean. ReadHeader(Stream,...) already documents its two parameters.

The four vendored ports must stay verbatim for byte-for-byte chdman parity,
so inspecting them only invites "fixes" that would break the guarantee. Skip
VendoredFlac, VendoredLZMA, VendoredZLib and VendoredZSTD wholesale (projects
and sources) with --exclude="Vendored*/**" instead of only their .cs files,
and spell the rule out in AGENTS.md and docs/building.md.

…isabled

GitHub returns 404 from the dependency-graph API for this repository and does
not expose a way to enable the graph for user-owned repositories, so the
review action could only ever fail with "not supported on this repository".

Probe the SBOM endpoint first: when the graph is unavailable, emit a warning
annotation and skip the review so the check reflects reality. Enabling the
graph in Settings > Code security and analysis restores enforcement with no
workflow change.