Support configurable timeouts for thread shell commands (#41384)

## What changed

- Add an optional `timeoutMs` parameter to `thread/shellCommand` and propagate it to user shell execution.
- Preserve the one-hour default when the parameter is omitted or `null`, allow longer deadlines, and treat `0` as an immediate timeout.
- Reject negative or otherwise invalid values before execution. Timing out an auxiliary shell command leaves its active turn running.

## Testing

- Cover default, extended, immediate, invalid, standalone, active-turn, and interruption behavior.

GitOrigin-RevId: d72f67793d9766b7383f28d30140270a4a76a495

codex-rs/app-server/src/request_processors/thread_processor.rs

@@ -2426,12 +2426,26 @@ impl ThreadRequestProcessor {
         request_id: &ConnectionRequestId,
         params: ThreadShellCommandParams,
     ) -> Result<ThreadShellCommandResponse, JSONRPCErrorError> {
-        let ThreadShellCommandParams { thread_id, command } = params;
+        let ThreadShellCommandParams {
+            thread_id,
+            command,
+            timeout_ms,
+        } = params;
         let command = command.trim().to_string();
         if command.is_empty() {
             return Err(invalid_request("command must not be empty"));
         }
 
+        let timeout_ms = timeout_ms
+            .map(|timeout_ms| {
+                u64::try_from(timeout_ms).map_err(|_| {
+                    invalid_params(format!(
+                        "thread/shellCommand timeoutMs must be non-negative, got {timeout_ms}"
+                    ))
+                })
+            })
+            .transpose()?;
+
         let (_, thread) = self.load_thread(&thread_id).await?;
         ensure_direct_input_allowed(thread.as_ref()).await?;
 
@@ -2449,7 +2463,10 @@ impl ThreadRequestProcessor {
         self.submit_core_op(
             request_id,
             thread.as_ref(),
-            Op::RunUserShellCommand { command },
+            Op::RunUserShellCommand {
+                command,
+                timeout_ms,
+            },
         )
         .await
         .map_err(|err| internal_error(format!("failed to start shell command: {err}")))?;