docs(standards): rebase cross-kind wiki links via MkDocs hook

The standards wiki links to the sibling library reference with ../lib/... paths. Add src/hooks.py and enable it in mkdocs.wiki.yml so those links climb to the repo root and resolve to /standards/lib/... under directory URLs.

standards/wiki/01_overview/index.html

@@ -671,7 +671,7 @@ port/adapter binding, performed by the composition root at startup.</p>
 <li><strong>Spec-first.</strong> The HTTP contract is declared in <code>openapi.yaml</code>; route
    handlers are looked up by <code>operationId</code>. There are no decorator routers.</li>
 <li><strong>Reuse the libraries.</strong> Orchestration, DI, Mongo repositories, ingestion,
-   auth, and docs come from internal libraries — see the <a href="../lib/13_library_registry/">Library
+   auth, and docs come from internal libraries — see the <a href="../../lib/13_library_registry/">Library
    Registry</a>.</li>
 <li><strong>Explicit state machines.</strong> Long-running work moves through explicit,
    durable statuses and can pause for human input.</li>