Comprehensive platform review: security fixes, query optimization, UI improvements, and code cleanup

Security (Critical/High):
- Fix path traversal bypass in local storage provider (path.resolve + prefix check)
- Fix timing-unsafe HMAC comparison (crypto.timingSafeEqual)
- Add auth + ownership checks to email API routes (verify-credentials, change-password)
- Remove hardcoded secret key fallback in local storage provider
- Add production credential check for MinIO (fail loudly if not set)
- Remove DB error details from health check response
- Add stricter rate limiting on application submissions (5/hour)
- Add rate limiting on email availability check (anti-enumeration)
- Change getAIAssignmentJobStatus to adminProcedure
- Block dangerous file extensions on upload
- Reduce project list max perPage from 5000 to 200

Query Optimization:
- Optimize analytics getProjectRankings with select instead of full includes
- Fix N+1 in mentor.getSuggestions (batch findMany instead of loop)
- Use _count for files instead of fetching full file records in project list
- Switch to bulk notifications in assignment and user bulk operations
- Batch filtering upserts (25 per transaction instead of all at once)

UI/UX:
- Replace Inter font with Montserrat in public layout (brand consistency)
- Use Logo component in public layout instead of placeholder
- Create branded 404 and error pages
- Make admin rounds table responsive with mobile card layout
- Fix notification bell paths to be role-aware
- Replace hardcoded slate colors with semantic tokens in admin sidebar
- Force light mode (dark mode untested)
- Adjust CardTitle default size
- Improve muted-foreground contrast for accessibility (A11Y)
- Move profile form state initialization to useEffect

Code Quality:
- Extract shared toProjectWithRelations to anonymization.ts (removed 3 duplicates)
- Remove dead code: getObjectInfo, isValidImageSize, unused batch tag functions, debug logs
- Remove unused twilio dependency
- Remove redundant email index from schema
- Add actual storage object deletion when file records are deleted
- Wrap evaluation submit + assignment update in
- Add comprehensive platform review document

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

src/server/routers/application.ts

@@ -7,6 +7,7 @@ import {
   notifyAdmins,
   NotificationTypes,
 } from '../services/in-app-notification'
+import { checkRateLimit } from '@/lib/rate-limit'
 
 // Zod schemas for the application form
 const teamMemberSchema = z.object({
@@ -153,6 +154,16 @@ export const applicationRouter = router({
       })
     )
     .mutation(async ({ ctx, input }) => {
+      // Stricter rate limit for application submissions: 5 per hour per IP
+      const ip = ctx.ip || 'unknown'
+      const submitRateLimit = checkRateLimit(`app-submit:${ip}`, 5, 60 * 60 * 1000)
+      if (!submitRateLimit.success) {
+        throw new TRPCError({
+          code: 'TOO_MANY_REQUESTS',
+          message: 'Too many application submissions. Please try again later.',
+        })
+      }
+
       const { roundId, data } = input
 
       // Verify round exists and is open
@@ -351,6 +362,16 @@ export const applicationRouter = router({
       })
     )
     .query(async ({ ctx, input }) => {
+      // Rate limit to prevent email enumeration
+      const ip = ctx.ip || 'unknown'
+      const emailCheckLimit = checkRateLimit(`email-check:${ip}`, 20, 15 * 60 * 1000)
+      if (!emailCheckLimit.success) {
+        throw new TRPCError({
+          code: 'TOO_MANY_REQUESTS',
+          message: 'Too many requests. Please try again later.',
+        })
+      }
+
       const existing = await ctx.prisma.project.findFirst({
         where: {
           roundId: input.roundId,