Function parseConfig

src/project-config.ts:111–139

* Read + JSON-parse a `codegraph.json` once and return its validated view. * Every failure mode degrades to the zero-config default — a missing file, bad * JSON, or a typo'd value never throws.

(file: string)

 * JSON, or a typo'd value never throws.
 */
function parseConfig(file: string): ParsedConfig {
  let raw: string;
  try {
    raw = fs.readFileSync(file, 'utf-8');
  } catch {
    return EMPTY_CONFIG;
  }

  let parsed: unknown;
  try {
    parsed = JSON.parse(raw);
  } catch (err) {
    logWarn(`Ignoring ${PROJECT_CONFIG_FILENAME}: not valid JSON`, {
      file,
      error: err instanceof Error ? err.message : String(err),
    });
    return EMPTY_CONFIG;
  }

  if (!parsed || typeof parsed !== 'object') return EMPTY_CONFIG;

  const extensions = extractExtensions(parsed, file);
  const includeIgnored = extractIncludeIgnored(parsed, file);
  const exclude = extractExclude(parsed, file);
  if (extensions === EMPTY_EXTENSIONS && includeIgnored.length === 0 && exclude.length === 0) {
    return EMPTY_CONFIG;
  }
  return { extensions, includeIgnored, exclude };
}

/**
 * Validate the `extensions` map. Every failure mode degrades to "no overrides