Update template and guidance

[alexandratran]

Integrates AI agent readiness features into the template so new sites start with these capabilities out of the box.

• Adds docusaurus-plugin-llms
• Adds docusaurus-plugin-copy-page-button, positioned via a swizzled DocItem/Layout component (src/theme/DocItem/Layout/)
• Adds scripts/copy-md-to-build.js post-build script that copies source .md files into the
  build output so agents can retrieve raw Markdown by appending .md to any doc URL
• Adds static/robots.txt
• Adds vercel.json headers and rewrites
• Adds .cursor rules and skills
• Adds AGENTS.md
• Adds docs/configure/agent-readiness.md to explain what's pre-configured and walks
  through all required customization steps for a new site

Also makes other updates:

• Adds @docusaurus/theme-mermaid (since we use it in most new sites)
• Adds PR and issue templates
• Updates list of maintained doc sites on homepage
• Updates docs/create/repo-structure.md to document all new files and folders

---

Note

Medium Risk
Changes the production build and documents public AI crawling/content-signal defaults; impact is mostly template and docs, but adopters must customize URLs and licensing signals before go-live.

Overview
This PR turns the docs-template into an AI-ready starter: new sites get LLM discovery, raw Markdown access, and Cursor/agent guardrails by default.

Runtime and build: docusaurus.config.js registers docusaurus-plugin-llms (generates /llms.txt and /llms-full.txt) and enables Mermaid via @docusaurus/theme-mermaid. The npm run build pipeline runs scripts/copy-md-to-build.js after Docusaurus so .md URLs serve source Markdown with an agent pointer to /llms.txt. A swizzled src/theme/DocItem/Layout adds the copy-page-as-Markdown control in the doc header.

Contributor and agent UX: Adds .cursor/rules/ (Diataxis structure, voice, Markdown, terminology, workflow), .cursor/skills/ (author-page, style-review), and root AGENTS.md. New docs/configure/agent-readiness.md documents what ships pre-wired and required per-site customization (SITE_URL, robots.txt sitemap, terminology, etc.).

GitHub and docs housekeeping: Issue forms (fix-content, new-content, site), PULL_REQUEST_TEMPLATE.md, and expanded docs/create/repo-structure.md for .cursor, AGENTS.md, scripts/, theme swizzles, and vercel.json agent headers/rewrites. docs/index.md updates the maintained-sites table (e.g. MetaMask maintainer wording; removes DIN and Phosphor rows).

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Project	Deployment	Actions	Updated (UTC)
docs-template	Ready	Preview, Comment	Jun 2, 2026 10:40pm

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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^{Reviewed by Cursor Bugbot for commit 4c2ae7b. Configure here.}

[bgravenorst]

lgtm