Add "local" chat channels with proximity-based messaging

Introduced a "local" channel type to restrict chat visibility based on player proximity, configurable via `LOCAL_DISTANCE`. Added channel spy functionality to monitor "local" messages. Updated constructors and configuration to support this new feature.

api/src/main/java/com/alttd/chat/config/Config.java

@@ -368,6 +368,8 @@ public final class Config {
     public static String CUSTOM_CHANNEL_TOGGLED = "<yellow>Toggled <channel> <status>.</yellow>";
     public static Component TOGGLED_ON = null;
     public static Component TOGGLED_OFF = null;
+    public static double LOCAL_DISTANCE;
+    public static String CHANNEL_SPY = "<i><gray>SPY:</gray> <dark_gray>(<dark_gray><sender> → <channel>) <message></dark_gray>";
     private static void chatChannels() {
         ConfigurationNode node = getNode("chat-channels");
         if (node.empty()) {
@@ -383,12 +385,16 @@ public final class Config {
             new CustomChannel(channelName,
                     getString(key + "format", ""),
                     getList(key + "servers", Collections.EMPTY_LIST),
-                    getBoolean(key + "proxy", false));
+                    getBoolean(key + "proxy", false),
+                    getBoolean(key + "local", false)
+            );
         }
 
         CUSTOM_CHANNEL_TOGGLED = getString("chat-channels-messages.channel-toggled", CUSTOM_CHANNEL_TOGGLED);
         TOGGLED_ON = Utility.parseMiniMessage(getString("chat-channels-messages.channel-on", "<green>on</green><gray>"));
         TOGGLED_OFF = Utility.parseMiniMessage(getString("chat-channels-messages.channel-off", "<red>off</red><gray>"));
+        LOCAL_DISTANCE = getDouble("chat-channels-messages.local-distance", 200.0);
+        CHANNEL_SPY = getString("chat-channels-messages.spy", CHANNEL_SPY);
     }
 
     public static String SERVERMUTEPERMISSION = "chat.command.mute-server";

api/src/main/java/com/alttd/chat/objects/channels/Channel.java

@@ -10,12 +10,14 @@ public class Channel {
     protected String channelName;
     protected String format;
     protected boolean proxy;
+    protected boolean local;
 
-    public Channel(String channelName, String format, boolean proxy) {
+    public Channel(String channelName, String format, boolean proxy, boolean local) {
         this.permission = "chat.channel." + channelName.toLowerCase();
         this.channelName = channelName;
         this.format = format;
         this.proxy = proxy;
+        this.local = local;
         channels.put(channelName.toLowerCase(), this);
     }
 
@@ -39,6 +41,10 @@ public class Channel {
         return proxy;
     }
 
+    public boolean isLocal() {
+        return local;
+    }
+
     public static Channel getChatChannel(String channelName) {
         return channels.get(channelName.toLowerCase());
     }

api/src/main/java/com/alttd/chat/objects/channels/CustomChannel.java

@@ -5,8 +5,8 @@ import java.util.*;
 public class CustomChannel extends Channel {
     private final List<String> servers;
 
-    public CustomChannel(String channelName, String format, List<String> servers, boolean proxy) {
-        super(channelName, format, proxy);
+    public CustomChannel(String channelName, String format, List<String> servers, boolean proxy, boolean local) {
+        super(channelName, format, proxy, local);
         this.permission = "chat.channel." + channelName.toLowerCase();
         this.channelName = channelName;
         this.format = format;

api/src/main/java/com/alttd/chat/objects/channels/DefaultChannel.java

@@ -2,6 +2,6 @@ package com.alttd.chat.objects.channels;
 
 public abstract class DefaultChannel extends Channel{
     public DefaultChannel(String channelName, String format, boolean proxy) {
-        super(channelName, format, proxy);
+        super(channelName, format, proxy, false);
     }
 }