Get us booting on a dedicated server

It doesn't appear that blocks are syncing, so we'll need to look into
that. Hopefully fixes #193

src/main/java/dan200/computercraft/ComputerCraft.java

@@ -36,6 +36,7 @@ import dan200.computercraft.shared.turtle.items.ItemTurtle;
 import dan200.computercraft.shared.turtle.upgrades.*;
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.ModInitializer;
+import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.resource.ReloadableResourceManager;
 import net.minecraft.util.Identifier;
 import org.apache.logging.log4j.LogManager;
@@ -196,7 +197,7 @@ public final class ComputerCraft implements ModInitializer
     public void onInitialize()
     {
         ComputerCraftProxyCommon.setup();
-        if( net.fabricmc.loader.api.FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT )
+        if( FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT )
         {
             ComputerCraftProxyClient.setup();
         }

src/main/java/dan200/computercraft/client/proxy/ComputerCraftProxyClient.java

@@ -7,6 +7,7 @@
 package dan200.computercraft.client.proxy;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.FrameInfo;
 import dan200.computercraft.client.ClientRegistry;
 import dan200.computercraft.client.gui.*;
 import dan200.computercraft.client.render.TileEntityCableRenderer;
@@ -24,6 +25,7 @@ import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
 import net.fabricmc.fabric.api.client.model.ModelLoadingRegistry;
 import net.fabricmc.fabric.api.client.render.BlockEntityRendererRegistry;
 import net.fabricmc.fabric.api.event.client.ClientSpriteRegistryCallback;
+import net.fabricmc.fabric.api.event.client.ClientTickCallback;
 
 public final class ComputerCraftProxyClient
 {
@@ -42,6 +44,8 @@ public final class ComputerCraftProxyClient
         ModelLoadingRegistry.INSTANCE.registerResourceProvider( loader -> ( name, context ) ->
             TurtleModelLoader.INSTANCE.accepts( name ) ? TurtleModelLoader.INSTANCE.loadModel( name ) : null
         );
+
+        ClientTickCallback.EVENT.register( client -> FrameInfo.onTick() );
     }
 
     private static void registerContainers()

src/main/java/dan200/computercraft/shared/network/NetworkHandler.java

@@ -17,6 +17,8 @@ import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
 import net.fabricmc.fabric.api.network.ClientSidePacketRegistry;
 import net.fabricmc.fabric.api.network.PacketContext;
 import net.fabricmc.fabric.api.network.ServerSidePacketRegistry;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.network.packet.CustomPayloadS2CPacket;
 import net.minecraft.entity.player.PlayerEntity;
@@ -45,8 +47,11 @@ public final class NetworkHandler
 
     public static void setup()
     {
-        ClientSidePacketRegistry.INSTANCE.register( ID, NetworkHandler::receive );
         ServerSidePacketRegistry.INSTANCE.register( ID, NetworkHandler::receive );
+        if( FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT )
+        {
+            ClientSidePacketRegistry.INSTANCE.register( ID, NetworkHandler::receive );
+        }
 
         // Server messages
         registerMainThread( 0, ComputerActionServerMessage::new );

src/main/java/dan200/computercraft/shared/proxy/ComputerCraftProxyCommon.java

@@ -11,7 +11,6 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.media.IMedia;
 import dan200.computercraft.api.peripheral.IPeripheralTile;
 import dan200.computercraft.api.turtle.event.TurtleEvent;
-import dan200.computercraft.client.FrameInfo;
 import dan200.computercraft.core.computer.MainThread;
 import dan200.computercraft.core.tracking.Tracking;
 import dan200.computercraft.shared.Registry;
@@ -35,7 +34,6 @@ import dan200.computercraft.shared.turtle.recipes.TurtleUpgradeRecipe;
 import dan200.computercraft.shared.util.ImpostorRecipe;
 import dan200.computercraft.shared.util.ImpostorShapelessRecipe;
 import dan200.computercraft.shared.util.TickScheduler;
-import net.fabricmc.fabric.api.event.client.ClientTickCallback;
 import net.fabricmc.fabric.api.event.server.ServerStartCallback;
 import net.fabricmc.fabric.api.event.server.ServerStopCallback;
 import net.fabricmc.fabric.api.event.server.ServerTickCallback;
@@ -109,10 +107,6 @@ public class ComputerCraftProxyCommon
     {
         CommandRegistry.INSTANCE.register( false, CommandComputerCraft::register );
 
-        ClientTickCallback.EVENT.register( client -> {
-            FrameInfo.onTick();
-        } );
-
         ServerTickCallback.EVENT.register( server -> {
             MainThread.executePendingTasks();
             ComputerCraft.serverComputerRegistry.update();