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/messages/messages.routes.ts

@@ -1,7 +1,6 @@
+import { createChildLogger } from "@bete/shared/logger";
 import type { Request, Response, Router } from "express";
 import express from "express";
-import { getPool } from "../../shared/database/index.js";
-import { createChildLogger } from "@bete/shared/logger";
 import { asyncHandler } from "../../shared/middlewares/index.js";
 import {
   handleGetAttachmentsByChannel,
@@ -85,7 +84,6 @@ export function createMessagesRouter(): Router {
     }),
   );
 
-
   // POST /api/messages/:id/reanalyze - Mark single message for re-analysis
   router.post(
     "/messages/:id/reanalyze",
@@ -104,20 +102,11 @@ export function createMessagesRouter(): Router {
 
       reanalyzeInFlight.add(id);
       try {
-        const pool = getPool();
-        await pool.query(
-          // Only revert to pending if the message is not currently being
-          // processed (pending) already — prevents write amplification when
-          // the recovery worker already picked it up between UI clicks.
-          `UPDATE messages SET ai_status = 'pending'
-           WHERE id = $1 AND ai_status != 'pending'`,
-          [id],
-        );
+        await messagesService.markForReanalysis(id);
       } finally {
         reanalyzeInFlight.delete(id);
       }
 
-      logger.debug({ id }, "Message marked for re-analysis");
       res.status(200).json({ ok: true });
     }),
   );
@@ -129,36 +118,7 @@ export function createMessagesRouter(): Router {
       const limit = Number(req.query.limit) || 20;
       const channelId = (req.query.channelId as string) || undefined;
 
-      const pool = getPool();
-
-      let sqlQuery: string;
-      let params: (string | number)[];
-      if (channelId) {
-        sqlQuery = `
-          SELECT id, guild_id, channel_id, user_id, username, avatar_url,
-                 content, type, created_at, ai_status, ai_severity,
-                 ai_confidence, ai_analysis
-          FROM messages
-          WHERE ai_status IN ('warn', 'flagged')
-            AND channel_id = $1
-          ORDER BY created_at DESC
-          LIMIT $2
-        `;
-        params = [channelId, limit];
-      } else {
-        sqlQuery = `
-          SELECT id, guild_id, channel_id, user_id, username, avatar_url,
-                 content, type, created_at, ai_status, ai_severity,
-                 ai_confidence, ai_analysis
-          FROM messages
-          WHERE ai_status IN ('warn', 'flagged')
-          ORDER BY created_at DESC
-          LIMIT $1
-        `;
-        params = [limit];
-      }
-
-      const { rows } = await pool.query(sqlQuery, params);
+      const rows = await messagesService.getReviewMessages(channelId, limit);
       logger.debug({ limit, channelId }, "Review query executed");
       res.json({ results: rows, limit, cursor: null });
     }),
@@ -168,7 +128,7 @@ export function createMessagesRouter(): Router {
   router.post(
     "/messages/:id/moderate",
     asyncHandler(async (req: Request, res: Response) => {
-      const id = req.params.id;
+      const id = String(req.params.id ?? "");
       if (!id) {
         res.status(400).json({ error: "MISSING_ID" });
         return;
@@ -196,20 +156,12 @@ export function createMessagesRouter(): Router {
       }
 
       // Fetch the message to get guild/user context
-      const pool = getPool();
-      const { rows } = await pool.query(
-        `SELECT id, guild_id, channel_id, thread_id, user_id, content
-         FROM messages WHERE id = $1`,
-        [id],
-      );
-
-      if (rows.length === 0) {
+      const msg = await messagesService.getMessageById(id).catch(() => null);
+      if (!msg) {
         res.status(404).json({ error: "MESSAGE_NOT_FOUND" });
         return;
       }
 
-      const msg = rows[0] as Record<string, unknown>;
-
       // Publish command to DG via Redis
       const { publishCommand } = await import("../../ws/redis-bridge.js");
       await publishCommand({
@@ -217,9 +169,9 @@ export function createMessagesRouter(): Router {
         type: "moderation:action",
         payload: {
           messageId: id,
-          guildId: String(msg.guild_id ?? ""),
-          channelId: (msg.thread_id as string) || String(msg.channel_id ?? ""),
-          userId: String(msg.user_id ?? ""),
+          guildId: msg.guild_id,
+          channelId: msg.thread_id || msg.channel_id,
+          userId: msg.user_id,
           actionType,
           reason: reason ?? "Manual moderation from dashboard",
           requestedAt: Date.now(),