perf(hooks): use direct require() instead of spawning child process

Invoke hook scripts directly via require() when they export a
run(rawInput) function, eliminating one Node.js process spawn per
hook invocation (~50-100ms).

Includes path traversal guard, timeouts, error logging, PR review
feedback, legacy hooks guard, normalized filePath, and restored
findProjectRoot config detection with package manager support.

scripts/lib/resolve-formatter.js

@@ -18,9 +18,29 @@ const binCache = new Map();
 
 // ── Public helpers ──────────────────────────────────────────────────
 
+// Markers that indicate a project root (formatter configs included so
+// repos without package.json are still detected correctly).
+const PROJECT_ROOT_MARKERS = [
+  'package.json',
+  'biome.json',
+  'biome.jsonc',
+  '.prettierrc',
+  '.prettierrc.json',
+  '.prettierrc.js',
+  '.prettierrc.cjs',
+  '.prettierrc.mjs',
+  '.prettierrc.yml',
+  '.prettierrc.yaml',
+  '.prettierrc.toml',
+  'prettier.config.js',
+  'prettier.config.cjs',
+  'prettier.config.mjs'
+];
+
 /**
- * Walk up from `startDir` until a directory containing package.json is found.
- * Returns `startDir` as fallback when no package.json exists above it.
+ * Walk up from `startDir` until a directory containing a known project
+ * root marker (package.json or formatter config) is found.
+ * Returns `startDir` as fallback when no marker exists above it.
  *
  * @param {string} startDir - Absolute directory path to start from
  * @returns {string} Absolute path to the project root
@@ -30,9 +50,11 @@ function findProjectRoot(startDir) {
 
   let dir = startDir;
   while (dir !== path.dirname(dir)) {
-    if (fs.existsSync(path.join(dir, 'package.json'))) {
-      projectRootCache.set(startDir, dir);
-      return dir;
+    for (const marker of PROJECT_ROOT_MARKERS) {
+      if (fs.existsSync(path.join(dir, marker))) {
+        projectRootCache.set(startDir, dir);
+        return dir;
+      }
     }
     dir = path.dirname(dir);
   }
@@ -59,6 +81,20 @@ function detectFormatter(projectRoot) {
     }
   }
 
+  // Check package.json "prettier" key before config files
+  try {
+    const pkgPath = path.join(projectRoot, 'package.json');
+    if (fs.existsSync(pkgPath)) {
+      const pkg = JSON.parse(fs.readFileSync(pkgPath, 'utf8'));
+      if (pkg.prettier != null) {
+        formatterCache.set(projectRoot, 'prettier');
+        return 'prettier';
+      }
+    }
+  } catch {
+    // Malformed package.json — continue to file-based detection
+  }
+
   const prettierConfigs = [
     '.prettierrc',
     '.prettierrc.json',
@@ -70,7 +106,7 @@ function detectFormatter(projectRoot) {
     '.prettierrc.toml',
     'prettier.config.js',
     'prettier.config.cjs',
-    'prettier.config.mjs',
+    'prettier.config.mjs'
   ];
   for (const cfg of prettierConfigs) {
     if (fs.existsSync(path.join(projectRoot, cfg))) {
@@ -83,14 +119,35 @@ function detectFormatter(projectRoot) {
   return null;
 }
 
+/**
+ * Resolve the runner binary and prefix args for the configured package
+ * manager (respects CLAUDE_PACKAGE_MANAGER env and project config).
+ *
+ * @param {string} projectRoot - Absolute path to the project root
+ * @returns {{ bin: string, prefix: string[] }}
+ */
+// Windows .cmd shim mapping for cross-platform safety
+const WIN_CMD_SHIMS = { npx: 'npx.cmd', pnpm: 'pnpm.cmd', yarn: 'yarn.cmd', bunx: 'bunx.cmd' };
+
+function getRunnerFromPackageManager(projectRoot) {
+  const isWin = process.platform === 'win32';
+  const { getPackageManager } = require('./package-manager');
+  const pm = getPackageManager({ projectDir: projectRoot });
+  const execCmd = pm?.config?.execCmd || 'npx';
+  const [rawBin = 'npx', ...prefix] = execCmd.split(/\s+/).filter(Boolean);
+  const bin = isWin ? WIN_CMD_SHIMS[rawBin] || rawBin : rawBin;
+  return { bin, prefix };
+}
+
 /**
  * Resolve the formatter binary, preferring the local node_modules/.bin
- * installation over npx to avoid package-resolution overhead.
+ * installation over the package manager exec command to avoid
+ * package-resolution overhead.
  *
  * @param {string} projectRoot - Absolute path to the project root
  * @param {'biome' | 'prettier'} formatter - Detected formatter name
- * @returns {{ bin: string, prefix: string[] }}
- *   `bin`    – executable path (absolute local path or npx/npx.cmd)
+ * @returns {{ bin: string, prefix: string[] } | null}
+ *   `bin`    – executable path (absolute local path or runner binary)
  *   `prefix` – extra args to prepend (e.g. ['@biomejs/biome'] when using npx)
  */
 function resolveFormatterBin(projectRoot, formatter) {
@@ -98,45 +155,36 @@ function resolveFormatterBin(projectRoot, formatter) {
   if (binCache.has(cacheKey)) return binCache.get(cacheKey);
 
   const isWin = process.platform === 'win32';
-  const npxBin = isWin ? 'npx.cmd' : 'npx';
 
   if (formatter === 'biome') {
-    const localBin = path.join(
-      projectRoot,
-      'node_modules',
-      '.bin',
-      isWin ? 'biome.cmd' : 'biome',
-    );
+    const localBin = path.join(projectRoot, 'node_modules', '.bin', isWin ? 'biome.cmd' : 'biome');
     if (fs.existsSync(localBin)) {
       const result = { bin: localBin, prefix: [] };
       binCache.set(cacheKey, result);
       return result;
     }
-    const result = { bin: npxBin, prefix: ['@biomejs/biome'] };
+    const runner = getRunnerFromPackageManager(projectRoot);
+    const result = { bin: runner.bin, prefix: [...runner.prefix, '@biomejs/biome'] };
     binCache.set(cacheKey, result);
     return result;
   }
 
   if (formatter === 'prettier') {
-    const localBin = path.join(
-      projectRoot,
-      'node_modules',
-      '.bin',
-      isWin ? 'prettier.cmd' : 'prettier',
-    );
+    const localBin = path.join(projectRoot, 'node_modules', '.bin', isWin ? 'prettier.cmd' : 'prettier');
     if (fs.existsSync(localBin)) {
       const result = { bin: localBin, prefix: [] };
       binCache.set(cacheKey, result);
       return result;
     }
-    const result = { bin: npxBin, prefix: ['prettier'] };
+    const runner = getRunnerFromPackageManager(projectRoot);
+    const result = { bin: runner.bin, prefix: [...runner.prefix, 'prettier'] };
     binCache.set(cacheKey, result);
     return result;
   }
 
-  const result = { bin: npxBin, prefix: [] };
-  binCache.set(cacheKey, result);
-  return result;
+  // Unknown formatter — return null so callers can handle gracefully
+  binCache.set(cacheKey, null);
+  return null;
 }
 
 /**
@@ -152,5 +200,5 @@ module.exports = {
   findProjectRoot,
   detectFormatter,
   resolveFormatterBin,
-  clearCaches,
-};
+  clearCaches
+};