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/backend/src/modules/mascot-chat/mascot-chat.service.ts

@@ -1,47 +1,25 @@
 import { createChildLogger } from "@bete/shared/logger";
 import { config } from "../../shared/config/index.js";
-import { getPool } from "../../shared/database/index.js";
+import type {
+  MascotChatContext,
+  MascotChatHistoryRow,
+  SaveConversationInput,
+} from "./mascot-chat.repository.js";
+import { mascotChatRepository } from "./mascot-chat.repository.js";
 
 const logger = createChildLogger("mascot-chat.service");
 
-export interface MascotChatContext {
-  messageCount?: number;
-  activeParticipants?: number;
-  lastActivity?: string;
-  topicsDiscussed?: string[];
-  guildId?: string;
-  channelId?: string;
-}
-
-export interface SaveConversationInput {
-  userId: string;
-  userMessage: string;
-  mascotResponse: string;
-  context?: MascotChatContext;
-  timestamp: Date;
-}
-
-export interface MascotChatHistoryRow {
-  id: string;
-  user_id: string;
-  user_message: string;
-  mascot_response: string;
-  context: MascotChatContext | null;
-  created_at: string;
-}
-
 class MascotChatService {
-  private initialized = false;
-
   async processMessage(
     message: string,
     context: MascotChatContext | undefined,
     userId: string,
   ): Promise<string> {
-    await this.ensureSchema();
-
     const recentContext = await this.getRecentConversationContext(userId);
-    const serverInsights = await this.getServerInsights(context);
+    const serverInsights = await mascotChatRepository.getServerInsights(
+      context?.guildId,
+      context?.channelId,
+    );
 
     // Build LLM messages
     const systemPrompt = this.buildSystemPrompt(serverInsights);
@@ -56,142 +34,30 @@ class MascotChatService {
   }
 
   async saveConversation(input: SaveConversationInput): Promise<void> {
-    await this.ensureSchema();
-    const pool = getPool();
-
-    await pool.query(
-      `
-        INSERT INTO mascot_chat_messages
-          (user_id, user_message, mascot_response, context, created_at)
-        VALUES ($1, $2, $3, $4::jsonb, $5)
-      `,
-      [
-        input.userId,
-        input.userMessage,
-        input.mascotResponse,
-        JSON.stringify(input.context ?? {}),
-        input.timestamp.toISOString(),
-      ],
-    );
+    await mascotChatRepository.saveConversation(input);
   }
 
   async getChatHistory(
     userId: string,
     limit: number,
   ): Promise<MascotChatHistoryRow[]> {
-    await this.ensureSchema();
-    const pool = getPool();
-
-    const { rows } = await pool.query<MascotChatHistoryRow>(
-      `
-        SELECT id, user_id, user_message, mascot_response, context, created_at
-        FROM mascot_chat_messages
-        WHERE user_id = $1
-        ORDER BY created_at DESC
-        LIMIT $2
-      `,
-      [userId, limit],
-    );
-
-    return rows.reverse();
+    return mascotChatRepository.getChatHistory(userId, limit);
   }
 
   async clearChatHistory(userId: string): Promise<void> {
-    await this.ensureSchema();
-    const pool = getPool();
-    await pool.query(`DELETE FROM mascot_chat_messages WHERE user_id = $1`, [
-      userId,
-    ]);
-  }
-
-  private async ensureSchema(): Promise<void> {
-    if (this.initialized) return;
-
-    const pool = getPool();
-    await pool.query(`
-      CREATE TABLE IF NOT EXISTS mascot_chat_messages (
-        id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
-        user_id TEXT NOT NULL,
-        user_message TEXT NOT NULL,
-        mascot_response TEXT NOT NULL,
-        context JSONB NOT NULL DEFAULT '{}'::jsonb,
-        created_at TIMESTAMPTZ NOT NULL DEFAULT now()
-      )
-    `);
-    await pool.query(`
-      CREATE INDEX IF NOT EXISTS idx_mascot_chat_messages_user_created
-      ON mascot_chat_messages (user_id, created_at DESC)
-    `);
-
-    this.initialized = true;
-    logger.info("Mascot chat schema ready");
+    await mascotChatRepository.clearChatHistory(userId);
   }
 
   private async getRecentConversationContext(
     userId: string,
   ): Promise<string[]> {
-    const history = await this.getChatHistory(userId, 3);
+    const history = await mascotChatRepository.getChatHistory(userId, 3);
     return history.flatMap((row) => [
       `User: ${row.user_message}`,
       `Mascot: ${row.mascot_response}`,
     ]);
   }
 
-  private async getServerInsights(context?: MascotChatContext) {
-    const pool = getPool();
-    const guildId = context?.guildId;
-    const channelId = context?.channelId;
-
-    try {
-      const params: string[] = [];
-      const clauses: string[] = [];
-      if (guildId) {
-        params.push(guildId);
-        clauses.push(`guild_id = $${params.length}`);
-      }
-      if (channelId) {
-        params.push(channelId);
-        clauses.push(`channel_id = $${params.length}`);
-      }
-      const where = clauses.length ? `WHERE ${clauses.join(" AND ")}` : "";
-
-      const { rows } = await pool.query<{
-        total_messages: number;
-        active_users: number;
-        flagged: number;
-        warned: number;
-      }>(
-        `
-          SELECT
-            COUNT(*)::int AS total_messages,
-            COUNT(DISTINCT user_id)::int AS active_users,
-            COUNT(*) FILTER (WHERE ai_status = 'flagged')::int AS flagged,
-            COUNT(*) FILTER (WHERE ai_status = 'warn')::int AS warned
-          FROM messages
-          ${where}
-        `,
-        params,
-      );
-
-      return (
-        rows[0] ?? {
-          total_messages: 0,
-          active_users: 0,
-          flagged: 0,
-          warned: 0,
-        }
-      );
-    } catch (error) {
-      logger.warn({ error }, "Failed to load mascot server insights");
-      return {
-        total_messages: context?.messageCount ?? 0,
-        active_users: context?.activeParticipants ?? 0,
-        flagged: 0,
-        warned: 0,
-      };
-    }
-  }
-
   private buildSystemPrompt(insights: {
     total_messages: number;
     active_users: number;