chore(docs): add hookdoc build workflow

[utkarshcloudinary]

Summary

Adds a GitHub Actions workflow to build and publish PHP hook documentation to GitHub Pages, replacing the need for a dedicated long-lived feature/documentation branch.

Changes

• .github/workflows/build-docs.yml — new workflow. Triggers:
  • Push to master
  • Release published
  • Manual dispatch (workflow_dispatch)
• hookdoc-conf.json — jsdoc config
• .hookdoc/layout.tmpl — hookdoc HTML template
• patches/wp-hookdoc+0.2.0.patch — patches wp-hookdoc@0.2.0 to accept standard PHPDoc tag syntax (PHPStan-clean)
• package.json:
  • Adds build:docs script (does NOT modify main build — keeps CI fast)
  • postinstall runs patch-package before composer install
  • New devDeps: jsdoc, patch-package, wp-hookdoc
• .gitignore — ignores generated docs/ output (published to gh-pages by workflow)

Verified locally

• npm install succeeds; patch-package applies cleanly
• npm run build:docs generates 113 documentation files
• wp.org deploy zip is unaffected (Gruntfile uses explicit allow-list)

Post-merge setup

One-time GitHub setup after merging to master:

• Settings → Pages → Source: gh-pages branch, / (root)
• No GH_PAT secret needed — uses built-in GITHUB_TOKEN

Why not update main build script?

The original feature/documentation branch made build also run build:docs, which would slow every CI run (lint, PR checks, package builds). Docs only need to build when publishing, so we isolate it to its own workflow.