fix(cli): ignore terminal focus reports (salvage of #16780)

Ghostty/macOS window or tab navigation (Cmd+Shift+[ / ], Alt+Tab,
etc.) can deliver terminal focus reports (CSI I / CSI O) to the
running TUI. prompt_toolkit does not map those sequences by default,
so its parser falls back to literal key presses (ESC, [, I/O) and
inserts `[I` / `[O` into the prompt buffer after the ESC byte is
handled.

Fix: register the two sequences as Keys.Ignore in ANSI_SEQUENCES at
parser level, plus a no-op kb.add(Keys.Ignore) handler so the
default self-insert path never inserts focus-report bytes.

Salvage notes: original PR put the helper in cli.py. Salvaged into
hermes_cli/pt_input_extras.py alongside install_shift_enter_alias /
install_ctrl_enter_alias to match the established pattern for
ANSI_SEQUENCES augmentation. setdefault → in-check so any prior user
registration wins.

Closes #16780

cli.py

@@ -74,10 +74,15 @@ except (ImportError, AttributeError):
     _STEADY_CURSOR = None
 
 try:
-    from hermes_cli.pt_input_extras import install_shift_enter_alias, install_ctrl_enter_alias
+    from hermes_cli.pt_input_extras import (
+        install_ctrl_enter_alias,
+        install_ignored_terminal_sequences,
+        install_shift_enter_alias,
+    )
     install_shift_enter_alias()
     install_ctrl_enter_alias()
-    del install_shift_enter_alias, install_ctrl_enter_alias
+    install_ignored_terminal_sequences()
+    del install_shift_enter_alias, install_ctrl_enter_alias, install_ignored_terminal_sequences
 except Exception:
     pass
 import threading
@@ -12717,7 +12722,21 @@ class HermesCLI:
         
         # Key bindings for the input area
         kb = KeyBindings()
-        
+
+        from prompt_toolkit.keys import Keys as _IgnoreKeys
+
+        @kb.add(_IgnoreKeys.Ignore, eager=True)
+        def handle_ignored_terminal_sequence(event):
+            """Consume parser-level ignored terminal sequences before self-insert.
+
+            install_ignored_terminal_sequences() in hermes_cli.pt_input_extras
+            registers focus reports (CSI I / CSI O) as Keys.Ignore at the
+            VT100 parser level. Without this no-op binding the default
+            self-insert path would still fire and the bytes would land in
+            the buffer.
+            """
+            return None
+
         def handle_enter(event):
             """Handle Enter key - submit input.