fix: tech debt batch 1 — TS errors, vulnerabilities, dead code

- Fixed 12 TypeScript errors across analytics.ts, observer-project-detail.tsx, bulk-upload/page.tsx, settings/profile/page.tsx
- npm audit: 8 vulnerabilities resolved (1 critical, 4 high, 3 moderate)
- Deleted 3 dead files: live-control.ts (618 lines), feature-flags.ts, file-type-categories.ts
- Removed typescript.ignoreBuildErrors: true — TS errors now block builds

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

next.config.ts

@@ -4,8 +4,7 @@ const nextConfig: NextConfig = {
   output: 'standalone',
   serverExternalPackages: ['@prisma/client', 'minio'],
   typescript: {
-    // We run tsc --noEmit separately before each push
-    ignoreBuildErrors: true,
+    ignoreBuildErrors: false,
   },
   experimental: {
     optimizePackageImports: [