Config: fail closed invalid config loads

src/config/config.ts

@@ -4,6 +4,7 @@ export {
   createConfigIO,
   getRuntimeConfigSnapshot,
   loadConfig,
+  readBestEffortConfig,
   parseConfigJson5,
   readConfigFileSnapshot,
   readConfigFileSnapshotForWrite,

src/config/io.ts

@@ -810,7 +810,7 @@ export function createConfigIO(overrides: ConfigIoDeps = {}) {
       }
       const error = err as { code?: string };
       if (error?.code === "INVALID_CONFIG") {
-        return {};
+        throw err;
       }
       deps.logger.error(`Failed to read config at ${configPath}`, err);
       return {};
@@ -1372,6 +1372,11 @@ export function loadConfig(): OpenClawConfig {
   return config;
 }
 
+export async function readBestEffortConfig(): Promise<OpenClawConfig> {
+  const snapshot = await readConfigFileSnapshot();
+  return snapshot.valid ? loadConfig() : snapshot.config;
+}
+
 export async function readConfigFileSnapshot(): Promise<ConfigFileSnapshot> {
   return await createConfigIO().readConfigFileSnapshot();
 }