fix: production readiness — resolve build, lint, and code quality issues

- Fix Next.js build failure: remove duplicate route at (dashboard)/listings/[id]
  that conflicted with (public)/listings/[id] (same URL path in two route groups)
- Fix 772 ESLint errors: auto-fix import ordering (import-x/order), remove unused
  imports/variables, convert empty interfaces to type aliases, replace require()
  with ESM imports, fix consistent-type-imports violations
- Add CLAUDE.md for developer onboarding documentation
- All checks pass: 0 lint errors, typecheck clean, 230 tests passing, build success

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/api/src/modules/shared/shared.module.ts

@@ -2,6 +2,7 @@ import { Global, type MiddlewareConsumer, Module, type NestModule, RequestMethod
 import { APP_FILTER } from '@nestjs/core';
 import { EventEmitterModule } from '@nestjs/event-emitter';
 import { makeCounterProvider } from '@willsoto/nestjs-prometheus';
+import { CacheService, CACHE_HIT_TOTAL, CACHE_MISS_TOTAL } from './infrastructure/cache.service';
 import { EventBusService } from './infrastructure/event-bus.service';
 import { GlobalExceptionFilter } from './infrastructure/filters/global-exception.filter';
 import { LoggerService } from './infrastructure/logger.service';
@@ -11,7 +12,6 @@ import { RequestLoggingMiddleware } from './infrastructure/middleware/request-lo
 import { SanitizeInputMiddleware } from './infrastructure/middleware/sanitize-input.middleware';
 import { PrismaService } from './infrastructure/prisma.service';
 import { RedisService } from './infrastructure/redis.service';
-import { CacheService, CACHE_HIT_TOTAL, CACHE_MISS_TOTAL } from './infrastructure/cache.service';
 
 @Global()
 @Module({