add --dangerously-bypass-hook-trust CLI flag (#21768)

# Why

Hook trust happens through the TUI in `/hooks` so it can block
non-interactive use cases. This flag will allow users that are using
codex headlessly to bypass hooks when they want to.

# What

This adds one invocation-scoped escape hatch.

- the CLI flag sets a runtime-only `bypass_hook_trust` override; there
is no durable `config.toml` setting
- hook discovery still respects normal enablement, so explicitly
disabled hooks remain disabled
- we show a `--dangerously-bypass-hook-trust is enabled. Enabled hooks
may run without review for this invocation.` message on startup so
accidental use is visible in both interactive and exec flows

This keeps “enabled” and “trusted” as separate concepts in the normal
path, while giving CI/E2E callers a stable way to opt into the
exceptional path when they already control the hook set.

codex-rs/tui/src/app/tests.rs

@@ -304,6 +304,18 @@ async fn ignore_same_thread_resume_allows_reattaching_displayed_inactive_thread(
     assert!(app.transcript_cells.is_empty());
 }
 
+#[test]
+fn bypass_hook_trust_startup_warning_snapshot() {
+    let rendered = lines_to_single_string(
+        &history_cell::new_warning_event(
+            "`--dangerously-bypass-hook-trust` is enabled. Enabled hooks may run without review for this invocation."
+                .to_string(),
+        )
+        .display_lines(/*width*/ 80),
+    );
+
+    assert_app_snapshot!("bypass_hook_trust_startup_warning", rendered);
+}
 #[tokio::test]
 async fn enqueue_primary_thread_session_replays_buffered_approval_after_attach() -> Result<()> {
     let (mut app, mut app_event_rx, _op_rx) = make_test_app_with_channels().await;

codex-rs/tui/src/lib.rs

@@ -928,6 +928,7 @@ pub async fn run_main(
         codex_linux_sandbox_exe: arg0_paths.codex_linux_sandbox_exe.clone(),
         main_execve_wrapper_exe: arg0_paths.main_execve_wrapper_exe.clone(),
         show_raw_agent_reasoning: cli.oss.then_some(true),
+        bypass_hook_trust: cli.bypass_hook_trust.then_some(true),
         additional_writable_roots: additional_dirs,
         ..Default::default()
     };

codex-rs/tui/src/snapshots/codex_tui__app__tests__bypass_hook_trust_startup_warning.snap

@@ -0,0 +1,6 @@
+---
+source: tui/src/app/tests.rs
+expression: rendered
+---
+⚠ `--dangerously-bypass-hook-trust` is enabled. Enabled hooks may run without
+  review for this invocation.