refactor: convert component structs to record structs

Game.Blackjack/Components/Card.cs

@@ -7,7 +7,7 @@ namespace Game.Blackjack;
 /// One entity per card.
 /// </summary>
 [MessagePackObject]
-public struct Card
+public record struct Card
 {
     [Key(0)] public Suit Suit;
     [Key(1)] public Rank Rank;

Game.Blackjack/Components/Holds.cs

@@ -8,7 +8,7 @@ namespace Game.Blackjack;
 /// representing that the hand holds this card.
 /// </summary>
 [MessagePackObject]
-public struct Holds : IRelationship
+public record struct Holds : IRelationship
 {
     [Key(0)] public Entity Source { get; set; }
     [Key(1)] public Entity Target { get; set; }

Game.Blackjack/Components/InDeck.cs

@@ -8,7 +8,7 @@ namespace Game.Blackjack;
 /// representing that the card is in the deck.
 /// </summary>
 [MessagePackObject]
-public struct InDeck : IRelationship
+public record struct InDeck : IRelationship
 {
     [Key(0)] public Entity Source { get; set; }
     [Key(1)] public Entity Target { get; set; }