refactor: consolidate config types and remove file-based config

Tickets: #2, #3

- Remove duplicate type definitions from shared/lib/config.ts
- Import types from schema files (game-settings.ts, guild-settings.ts)
- Add GuildConfig interface to guild-settings.ts schema
- Rename ModerationConfig to ModerationCaseConfig in moderation.service.ts
- Delete shared/config/config.json and shared/scripts/migrate-config-to-db.ts
- Update settings API to use gameSettingsService exclusively
- Return DB format (strings) from API instead of runtime BigInts
- Fix moderation service tests to pass config as parameter

Breaking Changes:
- Removes legacy file-based configuration system
- API now returns database format with string values for BigInt fields

web/src/routes/settings.routes.ts

@@ -7,13 +7,6 @@
 import type { RouteContext, RouteModule } from "./types";
 import { jsonResponse, errorResponse, withErrorHandling } from "./utils";
 
-/**
- * JSON replacer for BigInt serialization.
- */
-function jsonReplacer(_key: string, value: unknown): unknown {
-    return typeof value === "bigint" ? value.toString() : value;
-}
-
 /**
  * Settings routes handler.
  * 
@@ -32,26 +25,31 @@ async function handler(ctx: RouteContext): Promise<Response | null> {
 
     /**
      * @route GET /api/settings
-     * @description Returns the current bot configuration.
+     * @description Returns the current bot configuration from database.
      * Configuration includes economy settings, leveling settings,
      * command toggles, and other system settings.
-     * @response 200 - Full configuration object
+     * @response 200 - Full configuration object (DB format with strings for BigInts)
      * @response 500 - Error fetching settings
      * 
      * @example
      * // Response
      * {
-     *   "economy": { "dailyReward": 100, "streakBonus": 10 },
-     *   "leveling": { "xpPerMessage": 15, "levelUpChannel": "123456789" },
+     *   "economy": { "daily": { "amount": "100", "streakBonus": "10" } },
+     *   "leveling": { "base": 100, "exponent": 1.5 },
      *   "commands": { "disabled": [], "channelLocks": {} }
      * }
      */
     if (pathname === "/api/settings" && method === "GET") {
         return withErrorHandling(async () => {
-            const { config } = await import("@shared/lib/config");
-            return new Response(JSON.stringify(config, jsonReplacer), {
-                headers: { "Content-Type": "application/json" }
-            });
+            const { gameSettingsService } = await import("@shared/modules/game-settings/game-settings.service");
+            const settings = await gameSettingsService.getSettings();
+            
+            if (!settings) {
+                // Return defaults if no settings in DB yet
+                return jsonResponse(gameSettingsService.getDefaults());
+            }
+            
+            return jsonResponse(settings);
         }, "fetch settings");
     }
 
@@ -61,7 +59,7 @@ async function handler(ctx: RouteContext): Promise<Response | null> {
      * Only the provided fields will be updated; other settings remain unchanged.
      * After updating, commands are automatically reloaded.
      * 
-     * @body Partial configuration object
+     * @body Partial configuration object (DB format with strings for BigInts)
      * @response 200 - `{ success: true }`
      * @response 400 - Validation error
      * @response 500 - Error saving settings
@@ -69,19 +67,15 @@ async function handler(ctx: RouteContext): Promise<Response | null> {
      * @example
      * // Request - Only update economy daily reward
      * POST /api/settings
-     * { "economy": { "dailyReward": 150 } }
+     * { "economy": { "daily": { "amount": "150" } } }
      */
     if (pathname === "/api/settings" && method === "POST") {
         try {
-            const partialConfig = await req.json();
-            const { saveConfig, config: currentConfig } = await import("@shared/lib/config");
-            const { deepMerge } = await import("@shared/lib/utils");
-
-            // Merge partial update into current config
-            const mergedConfig = deepMerge(currentConfig, partialConfig);
-
-            // saveConfig throws if validation fails
-            saveConfig(mergedConfig);
+            const partialConfig = await req.json() as Record<string, unknown>;
+            const { gameSettingsService } = await import("@shared/modules/game-settings/game-settings.service");
+            
+            // Use upsertSettings to merge partial update
+            await gameSettingsService.upsertSettings(partialConfig as Record<string, unknown>);
 
             const { systemEvents, EVENTS } = await import("@shared/lib/events");
             systemEvents.emit(EVENTS.ACTIONS.RELOAD_COMMANDS);