feat(stealth): inject anti-detection patches in native Rust architecture

- Created cli/src/native/stealth.rs with stealth JS injection via CDP
- Extracted 32 patch IIFEs from TS stealth.ts into stealth_scripts.js
- Injected via Page.addScriptToEvaluateOnNewDocument on every launch/connect
- Added stealth Chrome args (disable AutomationControlled, use ANGLE GL)
- Auto-detects and cleans HeadlessChrome from User-Agent string
- Overrides navigator.userAgentData high-entropy hints
- Stealth enabled by default, disable with AGENT_BROWSER_STEALTH=0

Track 2 of native-stealth migration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli/src/native/actions.rs

@@ -33,6 +33,7 @@ use super::recording::{self, RecordingState};
 use super::screenshot::{self, ScreenshotOptions};
 use super::snapshot::{self, SnapshotOptions};
 use super::state;
+use super::stealth;
 use super::storage;
 use super::stream::{self, StreamServer};
 use super::tracing::{self as native_tracing, TracingState};
@@ -1550,6 +1551,7 @@ async fn auto_launch(state: &mut DaemonState) -> Result<(), String> {
         apply_launch_init_scripts(state).await;
         try_auto_restore_state(state).await;
         try_load_storage_state(state, &storage_state_path).await;
+        apply_stealth_to_browser(state).await;
         return Ok(());
     }
 
@@ -1563,6 +1565,7 @@ async fn auto_launch(state: &mut DaemonState) -> Result<(), String> {
         apply_launch_init_scripts(state).await;
         try_auto_restore_state(state).await;
         try_load_storage_state(state, &storage_state_path).await;
+        apply_stealth_to_browser(state).await;
         return Ok(());
     }
 
@@ -1633,6 +1636,8 @@ async fn auto_launch(state: &mut DaemonState) -> Result<(), String> {
     apply_launch_init_scripts(state).await;
     try_auto_restore_state(state).await;
     try_load_storage_state(state, &storage_state_path).await;
+    // Apply stealth anti-detection patches after browser is ready
+    apply_stealth_to_browser(state).await;
     Ok(())
 }
 
@@ -1683,6 +1688,36 @@ async fn apply_launch_init_scripts(state: &DaemonState) {
     }
 }
 
+/// Inject stealth scripts into the active browser session.
+/// Called after every successful launch / CDP connect / auto-connect.
+async fn apply_stealth_to_browser(state: &DaemonState) {
+    if env::var("AGENT_BROWSER_STEALTH").map(|v| v == "0").unwrap_or(false) {
+        return; // Explicitly disabled
+    }
+    let Some(ref mgr) = state.browser else {
+        return;
+    };
+    let Ok(session_id) = mgr.active_session_id() else {
+        return;
+    };
+    let locale = env::var("AGENT_BROWSER_LOCALE").ok();
+    if let Err(e) = stealth::apply_stealth(
+        &mgr.client,
+        session_id,
+        locale.as_deref(),
+    )
+    .await
+    {
+        eprintln!("[stealth] Failed to apply stealth patches: {}", e);
+    }
+    // Also inject into the current page (already loaded before our init script)
+    if let Err(e) =
+        stealth::apply_stealth_to_current_page(&mgr.client, session_id, locale.as_deref()).await
+    {
+        eprintln!("[stealth] Failed to patch current page: {}", e);
+    }
+}
+
 fn launch_options_from_env() -> LaunchOptions {
     let headed = env::var("AGENT_BROWSER_HEADED")
         .map(|v| v == "1" || v == "true")