chore(release): bump version to 0.0.12 and record the release

Record the published 0.0.12 release version in package.json and
package-lock.json, and add the release notes plus the handoff entry.

Published installer: release/publish/0.0.12/YCode-0.0.12-Setup-x64.exe
SHA-256 9ebeceb2505af9b3607887622e6ede0ab13c4e44afb63320ff5c4884df8329ea

Co-Authored-By: Claude Code <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ycode",
-  "version": "0.0.11",
+  "version": "0.0.12",
   "private": true,
   "description": "YCode - 个人 AI Agent 桌面应用（Electron）",
   "author": "YCode",