Fix syncing of colour between PocketBrain and item

 - Actually set colour when constructing the brain.
 - Sync it back after crafting, much like we do for upgrades (see
   dcc74e1) for more details.

We should take a proper look at this on 1.21.4 and make these methods
main-thread only, so we can sync immediately.

Fixes #2157

Author: SquidDev

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketBrain.java

@@ -44,11 +44,12 @@ public final class PocketBrain implements IPocketAccess {
     private int colour = -1;
     private int lightColour = -1;
 
-    public PocketBrain(PocketHolder holder, @Nullable UpgradeData<IPocketUpgrade> upgrade, ServerComputer.Properties properties) {
+    public PocketBrain(PocketHolder holder, @Nullable UpgradeData<IPocketUpgrade> upgrade, int colour, ServerComputer.Properties properties) {
         this.computer = new PocketServerComputer(this, holder, properties);
         this.holder = holder;
         this.position = holder.pos();
         this.upgrade = UpgradeData.copyOf(upgrade);
+        this.colour = colour;
         invalidatePeripheral();
     }
 

projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java

@@ -272,7 +272,7 @@ private PocketBrain getOrCreateBrain(ServerLevel level, PocketHolder holder, Ite
         }
 
         var brain = new PocketBrain(
-            holder, getUpgradeWithData(stack),
+            holder, getUpgradeWithData(stack), getColour(stack),
             ServerComputer.properties(getComputerID(stack), getFamily()).label(getLabel(stack))
         );
         var computer = brain.computer();
@@ -314,10 +314,14 @@ public void onCraftedBy(ItemStack stack, Level level, Player player) {
         // item. However, if we've just crafted the computer with an upgrade, we should sync the other way, and update
         // the computer.
         var server = level.getServer();
-        if (server != null) {
-            var computer = getServerComputer(server, stack);
-            if (computer != null) computer.getBrain().setUpgrade(getUpgradeWithData(stack));
-        }
+        if (server == null) return;
+
+        var computer = getServerComputer(server, stack);
+        if (computer == null) return;
+
+        var brain = computer.getBrain();
+        brain.setUpgrade(getUpgradeWithData(stack));
+        brain.setColour(getColour(stack));
     }
 
     // IComputerItem implementation