Function ensureGitignore

src/directory.ts:623–638

* Write `.codegraph/.gitignore` if it's absent, or upgrade a stale * CodeGraph-generated default in place; a user-customized file is left alone. * Best-effort — returns `false` only if a needed write failed.

(gitignorePath: string)

 * Best-effort — returns `false` only if a needed write failed.
 */
function ensureGitignore(gitignorePath: string): boolean {
  let existing: string | null;
  try {
    existing = fs.readFileSync(gitignorePath, 'utf-8');
  } catch {
    existing = null; // absent (ENOENT) or unreadable — (re)create below
  }
  // Current default or a user-authored file: nothing to do.
  if (existing !== null && !isStaleDefaultGitignore(existing)) return true;
  try {
    fs.writeFileSync(gitignorePath, GITIGNORE_CONTENT, 'utf-8');
    return true;
  } catch {
    return false;
  }
}

/**
 * Create the .codegraph directory structure