fix(tui): remove dead state fields and DRY up step helpers

- Remove `_shell_warning_active` and `_last_shell_warning` from
  CleverAgentsTuiApp.__init__, _show_shell_warning, and
  _clear_shell_warning — both fields were set but never consumed
- Extract shared `_submit_text` and `_submit_text_with_mocked_shell`
  into features/steps/_tui_helpers.py; update tui_app_coverage_steps
  and tui_shell_safety_steps to import from shared module, eliminating
  the duplicate definitions flagged across multiple review cycles

features/steps/_tui_helpers.py

@@ -0,0 +1,31 @@
+"""Shared TUI step-definition helpers."""
+
+from __future__ import annotations
+
+from types import SimpleNamespace
+from typing import Any
+from unittest.mock import patch
+
+from cleveragents.tui.input.shell_exec import ShellResult
+
+
+def _submit_text(context, text: str) -> None:
+    from cleveragents.tui.widgets.prompt import PromptInput
+
+    prompt = context._tui_app.query_one("#prompt", PromptInput)
+    prompt.value = text
+    event = SimpleNamespace()
+    context._tui_app.on_input_submitted(event)
+
+
+def _submit_text_with_mocked_shell(context, text: str, stdout: str = "mocked") -> None:
+    """Submit *text* while faking shell execution."""
+
+    def fake_run(command: str, **_: Any) -> ShellResult:
+        return ShellResult(command=command, exit_code=0, stdout=stdout, stderr="")
+
+    with patch(
+        "cleveragents.tui.input.shell_exec.run_shell_command",
+        side_effect=fake_run,
+    ):
+        _submit_text(context, text)

features/steps/tui_app_coverage_steps.py

@@ -5,12 +5,14 @@ import shutil
 import sys
 import tempfile
 from pathlib import Path
-from types import ModuleType, SimpleNamespace
+from types import ModuleType
 from typing import Any, cast
 from unittest.mock import MagicMock
 
 from behave import given, then, when
 
+from features.steps._tui_helpers import _submit_text
+
 # ---------------------------------------------------------------------------
 # Mock Textual infrastructure
 # ---------------------------------------------------------------------------
@@ -430,19 +432,6 @@ def step_persona_bar_shows_name(context):
     assert "scope refs" in bar._text
 
 
-# ---------------------------------------------------------------------------
-# on_input_submitted helpers
-# ---------------------------------------------------------------------------
-def _submit_text(context, text):
-    """Set prompt value and fire on_input_submitted."""
-    from cleveragents.tui.widgets.prompt import PromptInput
-
-    prompt = context._tui_app.query_one("#prompt", PromptInput)
-    prompt.value = text
-    event = SimpleNamespace()
-    context._tui_app.on_input_submitted(event)
-
-
 # ---------------------------------------------------------------------------
 # on_input_submitted: empty text (lines 144-150)
 # ---------------------------------------------------------------------------

features/steps/tui_shell_safety_steps.py

@@ -4,35 +4,13 @@ from __future__ import annotations
 
 import os
 from types import SimpleNamespace
-from typing import Any
 from unittest.mock import patch
 
 from behave import given, then, when
 
 from cleveragents.tui.input.modes import InputMode, ModeResult
-from cleveragents.tui.input.shell_exec import ShellResult
 
-
-def _submit_text(context, text: str) -> None:
-    from cleveragents.tui.widgets.prompt import PromptInput
-
-    prompt = context._tui_app.query_one("#prompt", PromptInput)
-    prompt.value = text
-    event = SimpleNamespace()
-    context._tui_app.on_input_submitted(event)
-
-
-def _submit_text_with_mocked_shell(context, text: str, stdout: str = "mocked") -> None:
-    """Submit *text* while faking shell execution."""
-
-    def fake_run(command: str, **_: Any) -> ShellResult:
-        return ShellResult(command=command, exit_code=0, stdout=stdout, stderr="")
-
-    with patch(
-        "cleveragents.tui.input.shell_exec.run_shell_command",
-        side_effect=fake_run,
-    ):
-        _submit_text(context, text)
+from features.steps._tui_helpers import _submit_text, _submit_text_with_mocked_shell
 
 
 @when('I submit "{text}" to the app')

src/cleveragents/tui/app.py

@@ -302,8 +302,6 @@ if _TEXTUAL_AVAILABLE:
             self._settings = get_settings()
             self._shell_warn_enabled = self._settings.shell_warn_dangerous
             self._allow_dangerous_shell = self._resolve_allow_dangerous_shell()
-            self._shell_warning_active = False
-            self._last_shell_warning: DangerousCommandWarning | None = None
             self._shell_safety: ShellSafetyService | None = (
                 ShellSafetyService(warn_callback=self._handle_shell_warning)
                 if self._shell_warn_enabled
@@ -621,8 +619,6 @@ if _TEXTUAL_AVAILABLE:
             shell_warning.display = True
             if hasattr(prompt, "add_class"):
                 prompt.add_class("dangerous")
-            self._last_shell_warning = warning
-            self._shell_warning_active = True
 
         def _clear_shell_warning(self) -> None:
             try:
@@ -635,8 +631,6 @@ if _TEXTUAL_AVAILABLE:
             shell_warning.display = False
             if hasattr(prompt, "remove_class"):
                 prompt.remove_class("dangerous")
-            self._last_shell_warning = None
-            self._shell_warning_active = False
 
         @staticmethod
         def _resolve_allow_dangerous_shell() -> bool: