refactor(core): update all classes for new config system + add tab completion

BREAKING CHANGE: Core classes updated to use new section-based config

Updated classes:
- Mine.java - uses RegionConfig, BlockConfig, new FillMode
- Mines.java - uses new ConfigLoader.ConfigLoadException
- MineFileManager.java - creates configs with new system
- MineRepository.java - uses new ConfigLoader
- MaskScanService.java - uses BlockKey for markers
- BukkitBlockSetter.java - uses Map<BlockKey, Double>

Handlers updated:
- ActionBarHandler.java - uses UIConfig with MiniMessage
- MineBlockHandler.java - uses ResetConfig
- MineRewardHandler.java - uses RewardConfig
- MineResetHandler.java - uses new config sections

Commands updated:
- MaskCommands.java - updated exception handling

Added:
- LoMinesTabCompleter.java - Bukkit tab completion for all commands
- RegistrationManager.registerTabCompleter() - registers tab completer

Removed:
- Old ConfigLoaderTest.java (uses deprecated config system)

All classes now use:
- Type-safe BlockKey instead of String
- Section-based config (region, blocks, reset, rewards, ui, teleport)
- Duration-based intervals instead of ticks
- MiniMessage formatting for action bar

src/main/java/dev/loki/lomines/command/MaskCommands.java

@@ -2,7 +2,7 @@ package dev.loki.lomines.command;
 
 import dev.loki.lomines.LoMinesPlugin;
 import dev.loki.lomines.core.Mines;
-import dev.loki.lomines.data.config.parser.ConfigParseException;
+import dev.loki.lomines.data.config.ConfigLoader;
 import dev.loki.lomines.util.ErrorHandler;
 import dev.loki.lomines.util.MessageFormatter;
 import dev.lolib.commands.annotation.Arg;
@@ -40,7 +40,7 @@ public class MaskCommands {
                                 + "'. Reset will spawn ore only at those positions."));
             } catch (IllegalArgumentException e) {
                 errorHandler.handleNotFound(sender, "Mine", name);
-            } catch (IOException | ConfigParseException e) {
+            } catch (IOException | ConfigLoader.ConfigLoadException e) {
                 errorHandler.handleError(sender, "Mask scan failed: " + e.getMessage(),
                         "maskscan failed for " + name, e);
             }