Add directional conversation focus shortcuts in workspace mode (#59287)

## What changed

- Add configurable `focus_pane_left` and `focus_pane_right` actions, defaulting to `leader left` / `leader h` and `leader right` / `leader l`.
- Move focus to the parent or open side conversation without reopening a hidden pane. Preserve the current interaction when no neighbor is available, and accept fresh typing after a no-op shortcut while suppressing reported key repeats.
- Expose the actions in the keymap picker and configuration schema, and prevent workspace-only pane bindings from claiming keys in classic mode.

## Testing

Add regression coverage for pane navigation, preserved transcript selection and search, fresh typing after a no-op, key capture, and binding conflicts and limits.

GitOrigin-RevId: 7f7629d15cffcd35d1353b36c5c9208dbb1034e8

codex-rs/tui/src/keymap/bindings.rs

@@ -107,7 +107,11 @@ impl KeymapActionId {
         self.context == KeymapContext::Global
             && matches!(
                 self.action,
-                "focus_main_composer" | "focus_sidebar_content" | "hide_pane"
+                "focus_main_composer"
+                    | "focus_sidebar_content"
+                    | "hide_pane"
+                    | "focus_pane_left"
+                    | "focus_pane_right"
             )
     }
 
@@ -306,6 +310,8 @@ define_runtime_action_bindings! {
         focus_main_composer,
         focus_sidebar_content,
         hide_pane,
+        focus_pane_left,
+        focus_pane_right,
         open_warnings => runtime_only,
         open_external_editor,
         copy,

codex-rs/tui/src/keymap/chords.rs

@@ -56,6 +56,7 @@ const TRANSCRIPT_ACTIONS: u32 = 1 << 20;
 const BACKEND_CYCLING: u32 = 1 << 21;
 const SIDE_PANE: u32 = 1 << 22;
 const MAIN_COMPOSER_FOCUS: u32 = 1 << 23;
+const PANE_DIRECTION: u32 = 1 << 24;
 
 const TRANSCRIPT_BROWSING: u32 = 1 << 14;
 
@@ -158,6 +159,10 @@ impl KeymapContextSet {
         }
     }
 
+    pub(crate) const fn with_pane_directions(self) -> Self {
+        Self(self.0 | PANE_DIRECTION)
+    }
+
     pub(crate) const fn with_main_composer_focus(self) -> Self {
         Self(self.0 | MAIN_COMPOSER_FOCUS)
     }
@@ -172,10 +177,10 @@ impl KeymapContextSet {
             return self.0 & BACKEND_CYCLING != 0;
         }
         if action.is_side_pane() {
-            let required = if action.action == "focus_main_composer" {
-                MAIN_COMPOSER_FOCUS
-            } else {
-                SIDE_PANE
+            let required = match action.action {
+                "focus_pane_left" | "focus_pane_right" => PANE_DIRECTION,
+                "focus_main_composer" => MAIN_COMPOSER_FOCUS,
+                _ => SIDE_PANE,
             };
             return self.0 & required != 0;
         }

codex-rs/tui/src/keymap/chords/leader_defaults.rs

@@ -26,15 +26,20 @@ pub(in crate::keymap) fn register(
             .filter(|binding| binding.is_leader())
             .count(),
     );
+    use KeyCode::Char;
     use KeymapContext::Chat;
     use KeymapContext::Global;
-    for (context, name, completion) in [
-        (Global, "change_host", 'b'),
-        (Global, "select_transcript", '['),
-        (Chat, "open_presets", 'p'),
-        (Global, "focus_main_composer", 'c'),
-        (Global, "focus_sidebar_content", 's'),
-        (Global, "hide_pane", '-'),
+    for (context, name, completion, spec) in [
+        (Global, "change_host", Char('b'), "b"),
+        (Global, "select_transcript", Char('['), "["),
+        (Chat, "open_presets", Char('p'), "p"),
+        (Global, "focus_main_composer", Char('c'), "c"),
+        (Global, "focus_sidebar_content", Char('s'), "s"),
+        (Global, "hide_pane", Char('-'), "-"),
+        (Global, "focus_pane_left", KeyCode::Left, "left"),
+        (Global, "focus_pane_left", Char('h'), "h"),
+        (Global, "focus_pane_right", KeyCode::Right, "right"),
+        (Global, "focus_pane_right", Char('l'), "l"),
     ] {
         if remaining == 0 {
             break;
@@ -56,9 +61,9 @@ pub(in crate::keymap) fn register(
                 action,
                 chord: KeyChord {
                     prefix,
-                    completion: crate::key_hint::plain(KeyCode::Char(completion)),
+                    completion: crate::key_hint::plain(completion),
                 },
-                spec: format!("leader {completion}"),
+                spec: format!("leader {spec}"),
             };
             if !resolved.chords.bindings.iter().any(|existing| {
                 binding.overlaps(existing.action) && existing.chord == binding.chord

codex-rs/tui/src/keymap/chords_tests.rs

@@ -187,6 +187,42 @@ fn allows_shared_prefixes_with_distinct_completions() {
     config.global.copy = Some(binding("ctrl-x ctrl-o"));
 
     RuntimeKeymap::from_config(&config).expect("prefix trie can branch on the second stroke");
+
+    // With 16 leaders and 56 explicit completions, only eight more aliases fit per leader.
+    let mut config = TuiKeymap::default();
+    config.global.leader = Some(KeybindingsSpec::Many(
+        (1..=16)
+            .map(|n| KeybindingSpec(format!("super-f{n}")))
+            .collect(),
+    ));
+    config.global.open_transcript = Some(KeybindingsSpec::Many(
+        ["", "shift-", "alt-"]
+            .into_iter()
+            .flat_map(|modifier| {
+                (1..=19).map(move |n| KeybindingSpec(format!("leader {modifier}f{n}")))
+            })
+            .take(56)
+            .collect(),
+    ));
+    let runtime = RuntimeKeymap::for_session(&config, /*workspace*/ true).unwrap();
+    assert_eq!(
+        runtime
+            .chords
+            .bindings
+            .iter()
+            .filter(|b| b.is_leader())
+            .count(),
+        super::MAX_LEADER_CHORD_BINDINGS
+    );
+    assert_eq!(
+        crate::keymap_setup::active_binding_specs(&runtime, "global", "focus_pane_left").unwrap(),
+        ["leader left", "leader h"]
+    );
+    assert!(
+        runtime
+            .primary_hint(KeymapContext::Global, "focus_pane_right")
+            .is_none()
+    );
 }
 
 #[test]