Python: Harness console for python (#6312)

* Add initial harness console for python

* Add textual to project

* Add planning and approval flows with list selector

* Address PR comments

* Fix list selection bug

* Fix PR #6312 round 2 review comments

- Escape untrusted agent text with rich.markup.escape() in observers
  (text_output, planning_output, reasoning_display) to prevent markup injection
- Remove non-functional 'Always approve' choices from tool_approval.py
  (framework lacks CreateAlwaysApproveToolResponse support)
- Remove textual from root pyproject.toml dev deps (sample-specific)
- Add PEP 723 inline script metadata to harness_research.py
- Narrow except Exception to except NoMatches in list_selection.py

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Fix build error

* Fix build errors

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

python/samples/02-agents/harness/console/commands/todo_handler.py

@@ -0,0 +1,66 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+"""Todo command handler — /todos to display the todo list."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from .base import CommandHandler
+
+if TYPE_CHECKING:
+    from agent_framework import AgentSession, TodoProvider
+
+    from ..state_driver import IUXStateDriver
+
+
+class TodoCommandHandler(CommandHandler):
+    """Handle the /todos command to display the current todo list."""
+
+    def __init__(self, todo_provider: TodoProvider | None) -> None:
+        """Initialize with the todo provider.
+
+        Args:
+            todo_provider: The todo provider, or None if not available.
+        """
+        self._todo_provider = todo_provider
+
+    def get_help_text(self) -> str | None:
+        """Return help text, or None if todo provider is unavailable."""
+        if self._todo_provider is None:
+            return None
+        return "/todos (show todo list)"
+
+    async def try_handle(
+        self,
+        user_input: str,
+        session: AgentSession,
+        ux: IUXStateDriver,
+    ) -> bool:
+        """Handle /todos by displaying the todo list."""
+        if user_input.strip().lower() != "/todos":
+            return False
+
+        if self._todo_provider is None:
+            ux.append_info_line("TodoProvider is not available.")
+            return True
+
+        todos = await self._todo_provider.store.load_items(
+            session, source_id=self._todo_provider.source_id
+        )
+
+        if not todos:
+            ux.append_info_line("No todos yet.")
+            return True
+
+        ux.append_info_line("── Todo List ──")
+        for item in todos:
+            status = "✓" if item.is_complete else "○"
+            color = "dim" if item.is_complete else None
+            description = f" — {item.description}" if item.description else ""
+            ux.append_info_line(
+                f"[{status}] #{item.id} {item.title}{description}",
+                color=color,
+            )
+
+        return True