feat: add TLDR ArgumentAction and Rich-compatible prompt styling

- Introduce `ArgumentAction.TLDR` for showing concise usage examples
- Add `rich_text_to_prompt_text()` to support Rich-style markup in all prompt_toolkit inputs
- Migrate all prompt-based Actions to use `prompt_message` with Rich styling support
- Standardize `CancelSignal` as the default interrupt behavior for prompt-driven Actions

falyx/bottom_bar.py

@@ -56,7 +56,7 @@ class BottomBar:
             Must return True if key is available, otherwise False.
     """
 
-    RESERVED_CTRL_KEYS = {"c", "d", "z"}
+    RESERVED_CTRL_KEYS = {"c", "d", "z", "v"}
 
     def __init__(
         self,