fix: remove shell:true default to fix command output

- Removed shell:true default that caused double shell wrapping
- This was causing echo and other commands to return empty output
- Now matches OpenClaw exec behavior which never uses shell:true

pcexec/src/index.ts

@@ -201,7 +201,8 @@ export async function pcexec(command: string, options: PcExecOptions = {}): Prom
     const spawnOptions: SpawnOptions = {
       cwd: options.cwd,
       env,
-      shell: options.shell ?? true,
+      // Don't use shell by default - we're already using bash -c explicitly
+      shell: options.shell,
       windowsHide: options.windowsHide,
       uid: options.uid,
       gid: options.gid,
@@ -327,7 +328,8 @@ export function pcexecSync(command: string, options: PcExecOptions = {}): PcExec
   const execOptions: any = {
     cwd: options.cwd,
     env,
-    shell: options.shell ?? true,
+    // Don't use shell by default
+    shell: options.shell,
     encoding: 'utf8',
     windowsHide: options.windowsHide,
     uid: options.uid,