feat: add MC 1.21.4 (protocol 769) support

Add complete protocol 769 support for Minecraft 1.21.4:

- Version constants: Add 769 to supported versions, MC_1_21_4_Version constant,
  and version string mappings (including 1.21.3 -> 768 compatibility)
- Item palette: 10 new items (Resin series + Eyeblossom), generated ItemPalette1214
- Entity palette: Remove CreakingTransient (149 entities, down from 150)
- Block palette: 10 new blocks with correct blockstate ID ranges from server data
- Packet palette: Serverbound packet ID reshuffling - PickItem split into
  PickItemFromBlock/PickItemFromEntity, new PlayerLoaded packet inserted after
  PlayerInput, subsequent IDs shifted accordingly. Clientbound unchanged.
- PlayerLoaded: Send empty PlayerLoaded packet after JoinGame processing (>= 1.21.4)
- EntityMetadata/DataComponents: Reuse 1.20.6 palettes (unchanged registries)
- Update all version guard checks from MC_1_21_2 to MC_1_21_4

Made-with: Cursor

MinecraftClient/Mapping/MaterialExtensions.cs

@@ -1,4 +1,4 @@
-namespace MinecraftClient.Mapping
+namespace MinecraftClient.Mapping
 {
     /// <summary>
     /// Defines extension methods for the Material enumeration
@@ -122,6 +122,7 @@
                 case Material.ChiseledPolishedBlackstone:
                 case Material.ChiseledQuartzBlock:
                 case Material.ChiseledRedSandstone:
+                case Material.ChiseledResinBricks:
                 case Material.ChiseledSandstone:
                 case Material.ChiseledStoneBricks:
                 case Material.ChorusFlower:
@@ -500,6 +501,8 @@
                 case Material.PottedBlueOrchid:
                 case Material.PottedBrownMushroom:
                 case Material.PottedCactus:
+                case Material.PottedCherrySapling:
+                case Material.PottedClosedEyeblossom:
                 case Material.PottedCornflower:
                 case Material.PottedDandelion:
                 case Material.PottedDarkOakSapling:
@@ -509,6 +512,7 @@
                 case Material.PottedJungleSapling:
                 case Material.PottedLilyOfTheValley:
                 case Material.PottedOakSapling:
+                case Material.PottedOpenEyeblossom:
                 case Material.PottedOrangeTulip:
                 case Material.PottedOxeyeDaisy:
                 case Material.PottedPinkTulip:
@@ -576,6 +580,10 @@
                 case Material.RedWool:
                 case Material.ReinforcedDeepslate:
                 case Material.RepeatingCommandBlock:
+                case Material.ResinBlock:
+                case Material.ResinBrickStairs:
+                case Material.ResinBrickWall:
+                case Material.ResinBricks:
                 case Material.RespawnAnchor:
                 case Material.RootedDirt:
                 case Material.Sand:
@@ -868,6 +876,7 @@
                 case Material.QuartzSlab:
                 case Material.RedNetherBrickSlab:
                 case Material.RedSandstoneSlab:
+                case Material.ResinBrickSlab:
                 case Material.SandstoneSlab:
                 case Material.SmoothQuartzSlab:
                 case Material.SmoothRedSandstoneSlab: