release: prepare Desktop 0.15.2 and Agent 0.15.0

Add bilingual notes for Story Graph reads, full follow-up editing, note capture, diagnostics and website updates. Preserve published 0.15.1 history and include reviewed Host/cloud plans as explicitly unimplemented documentation. Agent remains 0.15.0 and requires Desktop 0.15.2. Typecheck, lint, notes and website validation passed; current-source Host runtime checks made four real model requests. User requested full-suite validation in CI rather than waiting for the interrupted local run.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "goodbuddy",
-  "version": "0.15.1",
+  "version": "0.15.2",
   "private": true,
   "description": "Secure desktop AI workspace with controlled Agent Runtimes",
   "desktopName": "GoodBuddy",