docs: update docs/protocol-api.md with new sign for rearrange_hand

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: S1M0N38

docs/protocol-api.md

@@ -129,7 +129,7 @@ The following table details the parameters required for each function. Note that
 | `start_run`            | `deck` (string): Deck name<br>`stake` (number): Difficulty level 1-8<br>`seed` (string, optional): Seed for run generation<br>`challenge` (string, optional): Challenge name |
 | `skip_or_select_blind` | `action` (string): Either "select" or "skip"                                                                                                                                 |
 | `play_hand_or_discard` | `action` (string): Either "play_hand" or "discard"<br>`cards` (array): Card indices (0-indexed, 1-5 cards)                                                                   |
-| `rearrange_hand`       | `action` (string): Must be "rearrange_hand"<br>`cards` (array): Card indices (0-indexed, exactly `hand_size` elements)                                                       |
+| `rearrange_hand`       | `cards` (array): Card indices (0-indexed, exactly `hand_size` elements)                                                                                                     |
 | `shop`                 | `action` (string): Shop action to perform ("next_round")                                                                                                                     |
 
 ### Errors