[Refactor] Separate Round logic into its own file (#570)

* Everything works, need to clean up

* cleanup

* fix rebase issue

* clang format

* docs

* clang format

* clang format

* address part of review

* Protect against edge case when discarding at end of hand

* Protect undiscard against popping a discarded card that doesn't exist

* Protect against out of bounds access to the `played` cards stack

* fix condition in `select_four_of_a_kind_cards_in_played_hand`

* change `get_played_top() + 1` to `get_played_size()`

* move `can_play/discard_hand` functions to round.c

---------

Co-authored-by: MathisMartin31 <mathis.martin31@gmail.com>

include/game/common_ui.h

@@ -24,6 +24,8 @@ enum BackgroundId
     BG_MAIN_MENU
 };
 
+enum BackgroundId get_current_background(void);
+
 /**
  * Change the background
  *

include/game/round.h

@@ -0,0 +1,72 @@
+/**
+ * @file round.h
+ * @brief API relative to the Rounds we play
+ */
+
+#ifndef GAME_ROUND_H
+#define GAME_ROUND_H
+
+#include <stdbool.h>
+
+/**
+ * @brief Checks whether the score that would result from the current Chips and Mult exceeds the
+ *         current Blind's score requirement, and applies the flaming effect if needed.
+ */
+void toggle_flaming_score(void);
+
+/**
+ * @brief Get the index of the last played card
+ *
+ * @return int
+ */
+int get_played_top(void);
+
+/**
+ * @brief Get the number of cards played
+ *
+ * @return int
+ */
+int get_played_size(void);
+
+/**
+ * @brief Get the index of the last discarded card
+ *
+ * @return int
+ */
+int get_discard_top(void);
+
+/**
+ * @brief Get the index of the card that is currently being scored
+ *
+ * @return int
+ */
+int get_scored_card_index(void);
+
+/**
+ * @brief Set whether the current card should get triggered again
+ *
+ * @param new_retrigger true if the card should trigger again, false if not
+ */
+void set_retrigger(bool new_retrigger);
+
+/**
+ * @brief Change to the round card selection background
+ */
+void game_round_change_background_selecting(void);
+
+/**
+ * @brief Change to the round card playing background
+ */
+void game_round_change_background_playing(void);
+
+/**
+ * @brief Round state initialization
+ */
+void game_round_on_init(void);
+
+/**
+ * @brief Round state update
+ */
+void game_round_on_update(void);
+
+#endif // GAME_ROUND_H