feat(standards): MR-based tag strategy + repository inventory (registry://repos)

Versioning standard now documents the MR flow: bump pyproject.toml/VERSION and promote CHANGELOG in the MR (referencing the version/tag, not a commit id), merge/squash, then tag the resulting commit. Adds the agent-assisted tagging procedure (wait for the go-ahead, find the version-bump commit, tag only it, ask the user to push) to both the reference page and the releasing wiki runbook. Adds the repo inventory (src/repos.json -> mcp/repos.json), the registry://repos resource + list_repos tool, the 15_repository_inventory lib page, and two MCP prompts: compliance (remediate repos) and release (agent tagging).

standards/lib/index.html

@@ -496,6 +496,28 @@
   
   
   
+    <li class="md-nav__item">
+      <a href="15_repository_inventory/" class="md-nav__link">
+        
+  
+  
+  <span class="md-ellipsis">
+    Repository Inventory
+    
+  </span>
+  
+
+      </a>
+    </li>
+  
+
+    
+      
+      
+  
+  
+  
+  
     <li class="md-nav__item">
       <a href="12_genericity_matrix/" class="md-nav__link">
         
@@ -608,6 +630,8 @@ patterns, and the internal library catalog that agents consult while coding.</p>
 <li><strong>Drone Pipelines</strong> — the two CI shapes: a PyPI package or a Docker deployment.</li>
 <li><strong>Versioning &amp; Changelog</strong> — SemVer, the tag↔version contract, and the release
   changelog.</li>
+<li><strong>Repository Inventory</strong> — every covered repo, its type, version source, and
+  Drone shape.</li>
 <li><strong>Genericity Matrix</strong> — what is library-backed, template-provided, or authored.</li>
 <li><strong>Auth Integration</strong> — consuming the shared auth-server service (spec-driven,
   no auth code).</li>