feat: purge legacy agent hosts and land vault Chrome extension path

Retire ACP/Hermes/OpenCode surfaces and rename hermes_tools to
mnote_agent_tools so Page AI stays on Pi Lab only. Add Chrome vault
extension + extension token route, pre-release purge design, and soft-retire
legacy smokes for the small-group production cut.

scripts/task518-onlyoffice-real-iframe-session-scope-smoke.js

@@ -140,7 +140,7 @@ async function runBridgeExport(page, format = "html") {
 }
 
 async function postToolCall(context, payload) {
-  const response = await context.request.fetch(`${BASE_URL}/api/hermes/tools/mnote/call`, {
+  const response = await context.request.fetch(`${BASE_URL}/api/mnote/tools/call`, {
     method: "POST",
     headers: {
       "content-type": "application/json",