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/task-page-block-ai-conflict-idempotency-smoke.js

@@ -19,7 +19,7 @@ const OUT_DIR = path.join(process.cwd(), "tmp", "page-block-ai-conflict-idempote
 const CHROME_EXECUTABLE = process.env.PLAYWRIGHT_CHROME_EXECUTABLE || "";
 
 async function callMnoteTool(request, payload) {
-  return requestJson(request, "/api/hermes/tools/mnote/call", {
+  return requestJson(request, "/api/mnote/tools/call", {
     method: "POST",
     headers: { "x-mnote-actor-id": payload.actorId || "smoke-user" },
     data: payload,
@@ -27,7 +27,7 @@ async function callMnoteTool(request, payload) {
 }
 
 async function callMnoteToolRaw(request, payload) {
-  const response = await request.fetch(`${BASE_URL}/api/hermes/tools/mnote/call`, {
+  const response = await request.fetch(`${BASE_URL}/api/mnote/tools/call`, {
     method: "POST",
     headers: {
       "content-type": "application/json",