Remove deprecated log4j dependent methods in c.s.SettingsManager

And another one that is normally a bug to use, and a field that is
broken.

Enables `runtimeOnlyLog4j` in loom

build.gradle

@@ -13,7 +13,7 @@ group = project.maven_group
 
 loom {
 	accessWidenerPath = file("src/main/resources/carpet.accesswidener")
-	runtimeOnlyLog4j = false // Can be turned on after TriConsumer is no longer present in public API
+	runtimeOnlyLog4j = true
 }
 
 dependencies {

src/main/java/carpet/settings/SettingsManager.java

@@ -1,8 +1,6 @@
 package carpet.settings;
 
 import carpet.CarpetServer;
-import carpet.CarpetSettings;
-import carpet.api.settings.CarpetRule;
 import carpet.utils.CommandHelper;
 import com.mojang.brigadier.CommandDispatcher;
 import net.minecraft.commands.CommandBuildContext;
@@ -10,7 +8,6 @@ import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.flag.FeatureFlags;
-import org.apache.logging.log4j.util.TriConsumer;
 import java.util.Collection;
 import java.util.List;
 
@@ -22,12 +19,6 @@ import java.util.List;
 @SuppressWarnings("removal") // Gradle needs the explicit suppression
 public class SettingsManager extends carpet.api.settings.SettingsManager
 {
-    /**
-     * @deprecated Use {@link #locked()} instead
-     */
-    @Deprecated(forRemoval = true) //to private (or protected?)
-    public boolean locked;
-
     /**
      * Creates a new {@link SettingsManager} without a fancy name.
      * @see #SettingsManager(String, String, String)
@@ -57,61 +48,6 @@ public class SettingsManager extends carpet.api.settings.SettingsManager
         super(version, identifier, fancyName);
     }
 
-    /**
-     * <p>Adds a custom rule observer to changes in rules from 
-     * <b>this specific</b> {@link SettingsManager} instance.</p>
-     * 
-     * <p>This <b>outdated</b> method may not be able to listen to all {@link CarpetRule} implementations</p>
-     * 
-     * @see SettingsManager#registerGlobalRuleObserver(RuleObserver)
-     * 
-     * @param observer A {@link TriConsumer} that will be called with
-     *                 the used {@link CommandSourceStack}, the changed
-     *                 {@link ParsedRule} and a {@link String} being the
-     *                 value that the user typed.
-     * @deprecated Use {@link SettingsManager#registerRuleObserver(RuleObserver)} instead.
-     */
-    @Deprecated(forRemoval = true) //to remove
-    public void addRuleObserver(TriConsumer<CommandSourceStack, ParsedRule<?>, String> observer)
-    {
-        registerRuleObserver((source, rule, stringValue) -> {
-            if (rule instanceof ParsedRule<?> pr)
-                observer.accept(source, pr, stringValue);
-            else
-                CarpetSettings.LOG.warn("Failed to notify observer '" + observer.getClass().getName() + "' about rule change");
-        });
-        CarpetSettings.LOG.warn("""
-                Extension added outdated rule observer, this is deprecated and will crash in later carpet versions \
-                (way before the rest of the old settings api because of relying on log4j)!
-                The observer class name is '%s'""".formatted(observer.getClass().getName()));
-    }
-    
-    /**
-     * Adds a custom rule observer to changes in rules from 
-     * <b>any</b> registered {@link SettingsManager} instance.
-     * @see SettingsManager#addRuleObserver(TriConsumer)
-     * 
-     * @param observer A {@link TriConsumer} that will be called with
-     *                 the used {@link CommandSourceStack}, the changed
-     *                 {@link ParsedRule} and a {@link String} being the
-     *                 value that the user typed.
-     * @deprecated Use {@link SettingsManager#registerRuleObserver(RuleObserver)} instead, given this one can't deal with {@link CarpetRule}
-     */
-    @Deprecated(forRemoval = true) // to remove. This isn't really used anywhere
-    public static void addGlobalRuleObserver(TriConsumer<CommandSourceStack, ParsedRule<?>, String> observer)
-    {
-        registerGlobalRuleObserver((source, rule, stringValue) -> {
-            if (rule instanceof ParsedRule<?> pr)
-                observer.accept(source, pr, stringValue);
-            else
-                CarpetSettings.LOG.warn("Failed to notify observer '" + observer.getClass().getName() + "' about rule change");
-        });
-        CarpetSettings.LOG.warn("""
-                Extension added outdated rule observer, this is deprecated and will crash in later carpet versions \
-                (way before the rest of the old settings api because of relying on log4j)!
-                The observer class name is '%s'""".formatted(observer.getClass().getName()));
-    }
-
     /**
      * @deprecated Use {@link #identifier()} instead
      */
@@ -178,34 +114,6 @@ public class SettingsManager extends carpet.api.settings.SettingsManager
         return CommandHelper.canUseCommand(source, commandLevel);
     }
 
-    /**
-     * @param commandLevel A {@link String} being a permission level according to 
-     *                     Carpet's standard for permissions (either 0-4, a {@link boolean}, 
-     *                     or "ops".
-     * @return An {@link int} with the translated Vanilla permission level
-     * 
-     * @deprecated While there's not an API replacement for this (at least yet),
-     *             you can use the similar {@link CommandHelper#canUseCommand(CommandSourceStack, Object)} instead
-     * @apiNote Note that this method returns {@code 2} for {@code false} and {@code 0} for {@code true}.
-     * You probably want to use {@link #canUseCommand(CommandSourceStack, Object)}e
-     */
-    @Deprecated(forRemoval = true)
-    public static int getCommandLevel(String commandLevel)
-    {
-        switch (commandLevel)
-        {
-            case "true": return 2;
-            case "false": return 0;
-            case "ops": return 2; // typical for other cheaty commands
-            case "0":
-            case "1":
-            case "2":
-            case "3":
-            case "4":
-                return Integer.parseInt(commandLevel);
-        }
-        return 0;
-    }
     @Deprecated(forRemoval = true)
     public void registerCommand(CommandDispatcher<CommandSourceStack> dispatcher)
     {