feat: DID rotation + federation peer notification (Part 3)

- node.rotate-did: generates new Ed25519 keypair, signs rotation proof
  with old key, overwrites identity files, requires password
- federation.notify-did-change: broadcasts rotation proof to all
  trusted/observer peers over Tor
- federation.peer-did-changed: receiving side verifies rotation proof
  against known pubkey before updating peer's DID
- Rate-limited: 3/600s for rotation, 5/60s for peer notification
- Signature verification uses ed25519_dalek (constant-time)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

neode-ui/dev-dist/sw.js

@@ -82,7 +82,7 @@ define(['./workbox-21a80088'], (function (workbox) { 'use strict';
     "revision": "3ca0b8505b4bec776b69afdba2768812"
   }, {
     "url": "index.html",
-    "revision": "0.13rknjqo28"
+    "revision": "0.fo87inn2rb8"
   }], {});
   workbox.cleanupOutdatedCaches();
   workbox.registerRoute(new workbox.NavigationRoute(workbox.createHandlerBoundToURL("index.html"), {