refactor: comprehensive codebase cleanup and architecture hardening

- Sprint 1 (Quick Wins): Remove dead analytics modules, fix 4 unresolved
  imports, replace 3 console.warn with logger, remove mock-crc import
- Sprint 2 (Architecture): Create MascotChatRepository, AnalysisRepository,
  3 Zod schemas (mascot-chat, analysis, voice), deduplicate error classes,
  move 3 SQL queries from routes to repository
- Sprint 3 (Complexity): Replace 7 any types with proper interfaces,
  extract 6 helpers from prepareMediaMessage (CC 85 -> ~15)
- Sprint 4 (Config): Remove 22 dead env vars from .env, add 30 missing
  vars to .env.example, standardize naming

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/discord-gateway/src/app/bootstrap.ts

@@ -1,3 +1,4 @@
+import { ConfigError, DatabaseError } from "@bete/shared/errors";
 import { createChildLogger } from "@bete/shared/logger";
 import { Client } from "discord.js-selfbot-v13";
 import { startPendingAIAnalysisWorker } from "../modules/ai-moderation/aiAnalyzer.js";
@@ -19,7 +20,6 @@ import {
 } from "../shared/database/drizzle.js";
 import { runMigrations } from "../shared/database/migrate.js";
 import { createDiscordClientOptions } from "../shared/discord/clientOptions.js";
-import { ConfigError, DatabaseError } from "../shared/errors/errors.js";
 import { createGracefulShutdown } from "./shutdown.js";
 
 const logger = createChildLogger("discord-gateway");