Decouple projects from rounds with RoundProject join table

Projects now exist at the program level instead of being locked to a
single round. A new RoundProject join table enables many-to-many
relationships with per-round status tracking. Rounds have sortOrder
for configurable progression paths.

- Add RoundProject model, programId on Project, sortOrder on Round
- Migration preserves existing data (roundId -> RoundProject entries)
- Update all routers to query through RoundProject join
- Add assign/remove/advance/reorder round endpoints
- Add Assign, Advance, Remove Projects dialogs on round detail page
- Add round reorder controls (up/down arrows) on rounds list
- Show all rounds on project detail page

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

src/app/(admin)/admin/projects/[id]/assignments/page.tsx

@@ -96,7 +96,7 @@ export default function ProjectAssignmentsPage() {
           </div>
         </div>
         <Button asChild>
-          <Link href={`/admin/rounds/${project?.roundId}/assignments`}>
+          <Link href={`/admin/rounds/${project?.roundProjects?.[0]?.round?.id}/assignments`}>
             <Plus className="mr-2 h-4 w-4" />
             Manage in Round
           </Link>

src/app/(admin)/admin/projects/[id]/edit/page.tsx

@@ -121,7 +121,7 @@ function EditProjectContent({ projectId }: { projectId: string }) {
 
   // Fetch existing tags for suggestions
   const { data: existingTags } = trpc.project.getTags.useQuery({
-    roundId: project?.roundId,
+    roundId: project?.roundProjects?.[0]?.round?.id,
   })
 
   // Mutations
@@ -162,7 +162,7 @@ function EditProjectContent({ projectId }: { projectId: string }) {
         title: project.title,
         teamName: project.teamName || '',
         description: project.description || '',
-        status: project.status as UpdateProjectForm['status'],
+        status: (project.roundProjects?.[0]?.status ?? 'SUBMITTED') as UpdateProjectForm['status'],
         tags: project.tags || [],
       })
     }
@@ -197,6 +197,7 @@ function EditProjectContent({ projectId }: { projectId: string }) {
       teamName: data.teamName || null,
       description: data.description || null,
       status: data.status,
+      roundId: project?.roundProjects?.[0]?.round?.id,
       tags: data.tags,
     })
   }

src/app/(admin)/admin/projects/[id]/page.tsx

@@ -139,20 +139,29 @@ function ProjectDetailContent({ projectId }: { projectId: string }) {
             fallback="initials"
           />
           <div className="space-y-1">
-            <div className="flex items-center gap-2 text-sm text-muted-foreground">
-              <Link
-                href={`/admin/rounds/${project.round.id}`}
-                className="hover:underline"
-              >
-                {project.round.name}
-              </Link>
+            <div className="flex flex-wrap items-center gap-1 text-sm text-muted-foreground">
+              {project.roundProjects?.length > 0 ? (
+                project.roundProjects.map((rp, i) => (
+                  <span key={rp.round.id} className="flex items-center gap-1">
+                    {i > 0 && <span className="text-muted-foreground/50">/</span>}
+                    <Link
+                      href={`/admin/rounds/${rp.round.id}`}
+                      className="hover:underline"
+                    >
+                      {rp.round.name}
+                    </Link>
+                  </span>
+                ))
+              ) : (
+                <span>No round</span>
+              )}
             </div>
             <div className="flex items-center gap-3">
               <h1 className="text-2xl font-semibold tracking-tight">
                 {project.title}
               </h1>
-              <Badge variant={statusColors[project.status] || 'secondary'}>
-                {project.status.replace('_', ' ')}
+              <Badge variant={statusColors[project.roundProjects?.[0]?.status ?? 'SUBMITTED'] || 'secondary'}>
+                {(project.roundProjects?.[0]?.status ?? 'SUBMITTED').replace('_', ' ')}
               </Badge>
             </div>
             {project.teamName && (
@@ -504,7 +513,7 @@ function ProjectDetailContent({ projectId }: { projectId: string }) {
                 </CardDescription>
               </div>
               <Button variant="outline" size="sm" asChild>
-                <Link href={`/admin/rounds/${project.roundId}/assignments`}>
+                <Link href={`/admin/rounds/${project.roundProjects?.[0]?.round?.id}/assignments`}>
                   Manage
                 </Link>
               </Button>

src/app/(admin)/admin/projects/import/page.tsx

@@ -43,6 +43,7 @@ function ImportPageContent() {
   const rounds = programs?.flatMap((p) =>
     (p.rounds || []).map((r) => ({
       ...r,
+      programId: p.id,
       programName: `${p.year} Edition`,
     }))
   ) || []
@@ -170,6 +171,7 @@ function ImportPageContent() {
             </TabsList>
             <TabsContent value="csv" className="mt-4">
               <CSVImportForm
+                programId={selectedRound.programId}
                 roundId={selectedRoundId}
                 roundName={selectedRound.name}
                 onSuccess={() => {

src/app/(admin)/admin/projects/new/page.tsx

@@ -73,6 +73,7 @@ function NewProjectPageContent() {
   const rounds = programs?.flatMap((p) =>
     (p.rounds || []).map((r) => ({
       ...r,
+      programId: p.id,
       programName: `${p.year} Edition`,
     }))
   ) || []
@@ -117,6 +118,7 @@ function NewProjectPageContent() {
     })
 
     createProject.mutate({
+      programId: selectedRound!.programId,
       roundId: selectedRoundId,
       title: title.trim(),
       teamName: teamName.trim() || undefined,

src/app/(admin)/admin/projects/page.tsx

@@ -350,9 +350,9 @@ export default function ProjectsPage() {
                     </TableCell>
                     <TableCell>
                       <div>
-                        <p>{project.round.name}</p>
+                        <p>{project.roundProjects?.[0]?.round?.name ?? '-'}</p>
                         <p className="text-sm text-muted-foreground">
-                          {project.round.program?.name}
+                          {project.program?.name}
                         </p>
                       </div>
                     </TableCell>
@@ -365,9 +365,9 @@ export default function ProjectsPage() {
                     </TableCell>
                     <TableCell>
                       <Badge
-                        variant={statusColors[project.status] || 'secondary'}
+                        variant={statusColors[project.roundProjects?.[0]?.status ?? 'SUBMITTED'] || 'secondary'}
                       >
-                        {project.status.replace('_', ' ')}
+                        {(project.roundProjects?.[0]?.status ?? 'SUBMITTED').replace('_', ' ')}
                       </Badge>
                     </TableCell>
                     <TableCell className="relative z-10 text-right">
@@ -431,11 +431,11 @@ export default function ProjectsPage() {
                           </CardTitle>
                           <Badge
                             variant={
-                              statusColors[project.status] || 'secondary'
+                              statusColors[project.roundProjects?.[0]?.status ?? 'SUBMITTED'] || 'secondary'
                             }
                             className="shrink-0"
                           >
-                            {project.status.replace('_', ' ')}
+                            {(project.roundProjects?.[0]?.status ?? 'SUBMITTED').replace('_', ' ')}
                           </Badge>
                         </div>
                         <CardDescription>{project.teamName}</CardDescription>
@@ -445,7 +445,7 @@ export default function ProjectsPage() {
                   <CardContent className="space-y-3">
                     <div className="flex items-center justify-between text-sm">
                       <span className="text-muted-foreground">Round</span>
-                      <span>{project.round.name}</span>
+                      <span>{project.roundProjects?.[0]?.round?.name ?? '-'}</span>
                     </div>
                     <div className="flex items-center justify-between text-sm">
                       <span className="text-muted-foreground">Assignments</span>

src/app/(admin)/admin/projects/project-filters.tsx

@@ -72,7 +72,7 @@ export interface ProjectFilters {
 }
 
 interface FilterOptions {
-  rounds: Array<{ id: string; name: string; program: { name: string; year: number } }>
+  rounds: Array<{ id: string; name: string; sortOrder: number; program: { name: string; year: number } }>
   countries: string[]
   categories: Array<{ value: string; count: number }>
   issues: Array<{ value: string; count: number }>