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/shared/middlewares/index.ts

@@ -1,10 +1,10 @@
-import type { NextFunction, Request, Response } from "express";
 import {
   AppError,
   UnauthorizedError,
   ValidationError,
 } from "@bete/shared/errors";
 import { createChildLogger } from "@bete/shared/logger";
+import type { NextFunction, Request, Response } from "express";
 
 const logger = createChildLogger("middleware");
 
@@ -54,7 +54,11 @@ export function asyncHandler(
  * Validate that a value is a non-empty string, or throw a descriptive error.
  * Use for both route params and query string values.
  */
-export function requireParam(value: unknown, kind: string, name: string): string {
+export function requireParam(
+  value: unknown,
+  kind: string,
+  name: string,
+): string {
   if (typeof value !== "string" || value.length === 0) {
     throw new Error(`Missing ${kind}: ${name}`);
   }