Add docs theme override, manifest, and Pagefind pipeline for python-openapi.org

Adds the publishing-pipeline pieces required by the unified
python-openapi.org website shell:

- docs/_templates/layout.html: Sphinx layout override that injects
  the shared ecosystem banner and footer per docs-theme-contract.md
- docs/manifest.json: the manifest the shell consumes to resolve
  versions and the Pagefind bundle URL
- Makefile: docs-html, docs-pagefind, docs-manifest, docs-publish,
  and docs-cleanup targets used by the docs publishing pipeline
- .readthedocs.yaml: nodejs added under tools, post_build hook that
  runs `make docs-publish` and copies docs/_build/html/* into the
  RTD output, so each published build also exposes /pagefind/ and
  /manifest.json next to the HTML

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: p1c2u

docs/_templates/layout.html

@@ -0,0 +1,27 @@
+{# Shell-aware layout override for the Python OpenAPI Ecosystem website. #}
+{# Theme contract: docs-theme-contract.md (themeContractVersion 1).        #}
+{% extends "!layout.html" %}
+
+{% block extrahead %}
+  {{ super() }}
+  <meta name="ecosystem-shell" content="Python OpenAPI Ecosystem" />
+  <meta name="ecosystem-project" content="openapi-spec-validator" />
+  <meta data-theme-contract-version="1" />
+{% endblock %}
+
+{% block header %}
+  <aside class="ecosystem-shell-banner" aria-label="Python OpenAPI Ecosystem">
+    <a class="ecosystem-home" href="/" data-ecosystem-home="true">
+      ← Back to the Python OpenAPI Ecosystem
+    </a>
+    <span class="ecosystem-project-label" aria-current="page">openapi-spec-validator</span>
+  </aside>
+  {{ super() }}
+{% endblock %}
+
+{% block footer %}
+  {{ super() }}
+  <p class="ecosystem-footer-note" data-theme-contract-version="1">
+    Part of the <a href="/" class="ecosystem-home">Python OpenAPI Ecosystem</a>.
+  </p>
+{% endblock %}

docs/manifest.json

@@ -16,9 +16,9 @@
       "channel": "stable",
       "isLatestStable": true,
       "publicBasePath": "/openapi-spec-validator/docs/0.7.2/",
-      "originUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/",
-      "sitemapUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/sitemap.xml",
-      "searchBundleUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/pagefind/",
+      "originUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/",
+      "sitemapUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/sitemap.xml",
+      "searchBundleUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/pagefind/",
       "publishedAt": "2026-04-29T00:00:00Z"
     },
     {
@@ -27,9 +27,9 @@
       "channel": "next",
       "isLatestStable": false,
       "publicBasePath": "/openapi-spec-validator/docs/next/",
-      "originUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/",
-      "sitemapUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/sitemap.xml",
-      "searchBundleUrl": "https://openapi-spec-validator.readthedocs.io/en/spike-pagefind-smoke/pagefind/",
+      "originUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/",
+      "sitemapUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/sitemap.xml",
+      "searchBundleUrl": "https://openapi-spec-validator.readthedocs.io/en/latest/pagefind/",
       "publishedAt": "2026-04-29T00:00:00Z"
     }
   ]