Summary

• Fix the startup / first-typing regression in frontends/tuiapp_v2.py without touching other files.
• Ensure printable key handling in InputArea._on_key() goes through the same insertion path used by paste/newline via _insert_via_keyboard(), including a Windows-safe fallback.

Root cause

• In InputArea._on_key(), printable keys relied on super()._on_key(event).
• On some Windows key events, event.is_printable can be true while event.character is missing, which can cause the base TextArea insertion path to not apply that first key reliably.

Fix

• Updated frontends/tuiapp_v2.py:2334 inside InputArea._on_key():
  • Added a printable-key branch before the super() path.
  • Uses event.character first and falls back to event.key when character is None and key is a single character.
  • Routes the insert through _insert_via_keyboard().
  • Resets _history_index immediately for in-line editing (same intent as existing history-reset behavior).
• Left Enter/Shift+Enter submit behavior and existing history/palette routing unchanged.

Verification

• python -m py_compile frontends/tuiapp_v2.py
• python -c "import ast; ast.parse(open('frontends/tuiapp_v2.py', encoding='utf-8').read())"
• python frontends/tuiapp_v2.py — run attempt blocked by existing runtime config issue in this environment:
  • ZeroDivisionError: integer modulo by zero in agentmain.py:84 (load_llm_sessions() with empty LLM config list).
• Manual startup typing checks (repro steps from prompt) not executed due launch failure above.