feat(baoyu-electron-extract): add new skill to extract Electron app sources

Extracts resources and JavaScript from any installed Electron app's
app.asar. When .js.map files embed sourcesContent, restores the
original source tree (TypeScript/JSX included); otherwise formats
minified JS/CSS with Prettier in place. Always skips node_modules
and webpack/runtime/* entries.

Source-map paths are resolved relative to each .js.map file first,
so bundler-relative entries like ../../src/main.ts restore to
readable paths under restored/ instead of hashed placeholders.

Auto-discovers apps on macOS (/Applications, ~/Applications) and
Windows (%LOCALAPPDATA%\Programs, %PROGRAMFILES%, %PROGRAMFILES(X86)%,
%APPDATA%). On other platforms pass --asar <path> explicitly.

Safety: refuses to write to /, the user home, or the current working
directory, and refuses non-empty existing output dirs without --force.

.claude-plugin/marketplace.json

@@ -22,6 +22,7 @@
         "./skills/baoyu-danger-gemini-web",
         "./skills/baoyu-danger-x-to-markdown",
         "./skills/baoyu-diagram",
+        "./skills/baoyu-electron-extract",
         "./skills/baoyu-format-markdown",
         "./skills/baoyu-imagine",
         "./skills/baoyu-infographic",