Reset the terminal before opening the LXC shell

Write ESC c, the sequence `reset` sends, inside suspend() right before
ssh. The container shell then starts on a clean screen with no
leftover TUI terminal modes. It runs locally, so the container does
not need `reset` installed and `pct enter` is unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_app.py

@@ -907,3 +907,17 @@ async def test_table_reloads_after_shell(fake, monkeypatch):
         await press_t(app, pilot)
         await settle(app, pilot)
         assert fake.list_calls > before
+
+
+async def test_terminal_is_reset_inside_suspend_before_ssh(fake, monkeypatch):
+    # user request: a clean screen (and no leftover TUI terminal modes) in the container shell
+    fake.guests = [RUNNING_CT]
+    app = make_app()
+    events = patch_shell(monkeypatch, app)
+    resets = []
+    monkeypatch.setattr(
+        "cv4pve_tui.app._reset_terminal", lambda: resets.append(list(events))
+    )
+    async with app.run_test() as pilot:
+        await press_t(app, pilot)
+        assert resets == [[("enter", None)]]  # inside suspend, before ssh ran