fix: address 10 unresolved PR review threads

- README: add language specifier to fenced code block
- paths.ts: guard npmPackageRootDirectory() against bundle structure drift
- OpenCodeInstaller: resolve bundle from import.meta.url, not process.cwd()
- OpenCodeInstaller: log warnings on AGENTS.md injection failures
- WindsurfHooksInstaller: key registry by full workspace path, not basename
- uninstall.ts: poll health endpoint to wait for worker exit before file deletion
- uninstall.ts: call IDE-specific uninstallers (Gemini, Windsurf, OpenCode, OpenClaw, Codex)
- opencode-plugin: cap session tracking Map at 1000 entries with LRU eviction
- GeminiCliHooksInstaller: document intentional JSON double-escaping

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

src/npx-cli/utils/paths.ts

@@ -73,7 +73,14 @@ export function claudeMemDataDirectory(): string {
 export function npmPackageRootDirectory(): string {
   const currentFilePath = fileURLToPath(import.meta.url);
   // <pkg>/dist/npx-cli/index.js  ->  up 2 levels  ->  <pkg>
-  return join(dirname(currentFilePath), '..', '..');
+  const root = join(dirname(currentFilePath), '..', '..');
+  if (!existsSync(join(root, 'package.json'))) {
+    throw new Error(
+      `npmPackageRootDirectory: expected package.json at ${root}. ` +
+      `Bundle structure may have changed — update the path walk.`,
+    );
+  }
+  return root;
 }
 
 /**