fix(build): resolve Next.js build failures from invalid route exports

- Extract detectAuthAnomalies + THRESHOLDS from route.ts to detect.ts
  (Next.js rejects non-standard exports from route files)
- Add explicit RenderResult return type to test-utils customRender
- Skip ESLint during next build (runs separately via pnpm lint)
- Revert test file exclusions from tsconfig (breaks eslint parser)
- Update route.test.ts imports to match new file structure

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/next.config.ts

@@ -17,6 +17,11 @@ const nextConfig: NextConfig = {
     "@capakraken/staffing",
   ],
   typedRoutes: true,
+  eslint: {
+    // ESLint runs separately via `pnpm lint` — skip during `next build` to
+    // avoid plugin resolution issues in the build environment.
+    ignoreDuringBuilds: true,
+  },
   async redirects() {
     return [
       // Common URL alias — redirect to the real auth entry point
@@ -86,6 +91,7 @@ const nextConfig: NextConfig = {
 let exportedConfig: NextConfig = nextConfig;
 if (process.env.NODE_ENV === "production") {
   try {
+    // eslint-disable-next-line @typescript-eslint/no-require-imports
     const { withSentryConfig } = require("@sentry/nextjs");
     exportedConfig = withSentryConfig(nextConfig, {
       silent: true,