Several command permission fixes

- Attach permission checks to the first argument (so the literal
   command name) rather than the last argument. This fixes commands
   showing up when they shouldn't.

 - HelpingArgumentBuilder now inherits permissions of its leaf nodes.
   This only really impacts the "track" subcommand.

 - Don't autocomplete the computer selector for the "queue" subcommand.
   As everyone has permission for this command, it's possible to find
   all computer ids and labels in the world.

   I'm in mixed minds about this, but don't think this is an exploit -
   computer ids/labels are sent to in-range players so shouldn't be
   considered secret - but worth patching none-the-less.

src/main/java/dan200/computercraft/shared/command/CommandComputerCraft.java

@@ -7,10 +7,13 @@ package dan200.computercraft.shared.command;
 
 import com.mojang.brigadier.CommandDispatcher;
 import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.builder.RequiredArgumentBuilder;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.suggestion.Suggestions;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.core.metrics.Metrics;
+import dan200.computercraft.shared.command.arguments.ComputersArgumentType;
 import dan200.computercraft.shared.command.text.TableBuilder;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ServerComputer;
@@ -201,7 +204,10 @@ public final class CommandComputerCraft
 
             .then( command( "queue" )
                 .requires( UserLevel.ANYONE )
-                .arg( "computer", manyComputers() )
+                .arg(
+                    RequiredArgumentBuilder.<CommandSource, ComputersArgumentType.ComputersSupplier>argument( "computer", manyComputers() )
+                        .suggests( ( context, builder ) -> Suggestions.empty() )
+                )
                 .argManyValue( "args", StringArgumentType.string(), Collections.emptyList() )
                 .executes( ( ctx, args ) -> {
                     Collection<ServerComputer> computers = getComputersArgument( ctx, "computer" );