Remove dynamic form builder and complete RoundProject→roundId migration

Major cleanup and schema migration:
- Remove unused dynamic form builder system (ApplicationForm, ApplicationFormField, etc.)
- Complete migration from RoundProject junction table to direct Project.roundId
- Add sortOrder and entryNotificationType fields to Round model
- Add country field to User model for mentor matching
- Enhance onboarding with profile photo and country selection steps
- Fix all TypeScript errors related to roundProjects references
- Remove unused libraries (@radix-ui/react-toast, embla-carousel-react, vaul)

Files removed:
- admin/forms/* pages and related components
- admin/onboarding/* pages
- applicationForm.ts and onboarding.ts routers
- Dynamic form builder Prisma models and enums

Schema changes:
- Removed ApplicationForm, ApplicationFormField, OnboardingStep, ApplicationFormSubmission, SubmissionFile models
- Removed FormFieldType and SpecialFieldType enums
- Added Round.sortOrder, Round.entryNotificationType
- Added User.country

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

prisma/seed-candidatures.ts

@@ -321,7 +321,7 @@ async function main() {
       // Check if project already exists
       const existingProject = await prisma.project.findFirst({
         where: {
-          programId: program.id,
+          roundId: round.id,
           OR: [
             { title: projectName },
             { submittedByEmail: email },
@@ -365,7 +365,7 @@ async function main() {
       // Create project
       const project = await prisma.project.create({
         data: {
-          programId: program.id,
+          roundId: round.id,
           title: projectName,
           description: row['Comment ']?.trim() || null,
           competitionCategory: mapCategory(row['Category']),
@@ -391,15 +391,6 @@ async function main() {
         },
       })
 
-      // Create round-project association
-      await prisma.roundProject.create({
-        data: {
-          roundId: round.id,
-          projectId: project.id,
-          status: 'SUBMITTED',
-        },
-      })
-
       // Create team lead membership
       await prisma.teamMember.create({
         data: {
@@ -474,7 +465,7 @@ async function main() {
   console.log('\nBackfilling missing country codes...\n')
   let backfilled = 0
   const nullCountryProjects = await prisma.project.findMany({
-    where: { programId: program.id, country: null },
+    where: { roundId: round.id, country: null },
     select: { id: true, submittedByEmail: true, title: true },
   })