fix: OS release prep - bootstrap script, deps, docs

- Fix bootstrap script (.env.example.local → .env.example)
- Fix @langchain/core version conflict (^1.0.1 → ^0.3.0)
- Add settings:open event listener for LocalKeyGate button
- Pin Next.js to 15.1.3 (was "latest")
- Default runtime to 'local' mode
- Remove desktop app references from UI text
- Rewrite MCP docs for web-only context
- Add SECURITY.md, CODE_OF_CONDUCT.md, CHANGELOG.md
- Add docs/README.md, docs/TROUBLESHOOTING.md
- Update README with platform support table

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

next.config.js

@@ -12,8 +12,8 @@ const nextConfig = {
     ignoreBuildErrors: false,
   },
   eslint: {
-    // Temporarily ignore lint during builds for beta packaging
-    // TODO: Fix remaining ~150 lint errors in follow-up PR
+    // Temporarily ignore lint during builds
+    // TODO: Fix remaining lint errors in follow-up PR
     ignoreDuringBuilds: true,
   },
 }