fix: address PR review — shebang, double-escaping, data loss, uninstall scope

- Add shebang banner to NPX CLI esbuild config so npx claude-mem works
- Remove manual backslash pre-escaping in WindsurfHooksInstaller (JSON.stringify handles it)
- Scope cache deletion to claude-mem only, not entire vendor namespace
- Use getWorkerPort() in OpenCodeInstaller instead of hard-coded 37777
- Throw on corrupt JSON in readJsonSafe/readGeminiSettings/Windsurf to prevent data loss
- Fix Cursor install stub to warn instead of silently succeeding
- Fix Gemini uninstall to remove individual hooks within groups, not whole groups
- Update tests for new corrupt-file-throws behavior

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

scripts/build-hooks.js

@@ -200,6 +200,7 @@ async function buildHooks() {
       target: 'node18',
       format: 'esm',
       outfile: `${npxCliOutDir}/index.js`,
+      banner: { js: '#!/usr/bin/env node' },
       minify: true,
       logLevel: 'error',
       external: [