feat: render project averages to two decimals

Project-level averages (Raw + Balanced in the side panel, observer
project detail score card, observer preview dialog Avg Score) now
show two decimals (e.g. 8.33 instead of 8.0/8.3) so admins can see
the actual computed value. Per-juror individual scores keep one
decimal — they're submissions, not aggregates. ScorePill gains an
optional precision prop so call sites can opt into 2-decimal display
where the value is an aggregate.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/admin/round/ranking-dashboard.tsx

@@ -197,7 +197,7 @@ function SortableProjectRow({
           </div>
         ) : entry?.avgGlobalScore !== null && entry?.avgGlobalScore !== undefined ? (
           <span className="text-xs text-muted-foreground">
-            Avg {entry.avgGlobalScore.toFixed(1)}
+            Avg {entry.avgGlobalScore.toFixed(2)}
           </span>
         ) : null}
 
@@ -1067,12 +1067,12 @@ export function RankingDashboard({ competitionId: _competitionId, roundId }: Ran
                       <div className="flex items-baseline gap-4 flex-wrap">
                         <div className={`flex items-baseline gap-1 ${useBalanced ? 'text-muted-foreground' : 'font-semibold'}`}>
                           <span className="text-xs">Raw</span>
-                          <span className="text-lg tabular-nums">{raw != null ? raw.toFixed(1) : '—'}</span>
+                          <span className="text-lg tabular-nums">{raw != null ? raw.toFixed(2) : '—'}</span>
                           {!useBalanced && <span className="ml-1 text-[10px] text-muted-foreground">← used for ranking</span>}
                         </div>
                         <div className={`flex items-baseline gap-1 ${useBalanced ? 'font-semibold' : 'text-muted-foreground'}`}>
                           <span className="text-xs">Balanced</span>
-                          <span className="text-lg tabular-nums">{balanced != null ? balanced.toFixed(1) : '—'}</span>
+                          <span className="text-lg tabular-nums">{balanced != null ? balanced.toFixed(2) : '—'}</span>
                           {useBalanced && <span className="ml-1 text-[10px] text-muted-foreground">← used for ranking</span>}
                         </div>
                       </div>

src/components/observer/observer-project-detail.tsx

@@ -235,7 +235,7 @@ export function ObserverProjectDetail({
                 </div>
                 <p className="mt-2 text-4xl font-bold tabular-nums">
                   {stats.averageGlobalScore != null
-                    ? stats.averageGlobalScore.toFixed(1)
+                    ? stats.averageGlobalScore.toFixed(2)
                     : '-'}
                 </p>
                 <p className="text-xs text-muted-foreground">

src/components/observer/reports/project-preview-dialog.tsx

@@ -27,7 +27,7 @@ interface ProjectPreviewDialogProps {
   onOpenChange: (open: boolean) => void
 }
 
-function ScorePill({ score }: { score: number }) {
+function ScorePill({ score, precision = 1 }: { score: number; precision?: 1 | 2 }) {
   const bg = scoreGradient(score)
   const text = score >= 6 ? '#ffffff' : '#1a1a1a'
   return (
@@ -35,7 +35,7 @@ function ScorePill({ score }: { score: number }) {
       className="inline-flex items-center justify-center rounded-md px-2.5 py-1 text-sm font-bold tabular-nums"
       style={{ backgroundColor: bg, color: text }}
     >
-      {score.toFixed(1)}
+      {score.toFixed(precision)}
     </span>
   )
 }
@@ -117,7 +117,7 @@ export function ProjectPreviewDialog({ projectId, roundId, open, onOpenChange }:
                     <div className="rounded-md border p-3 text-center">
                       <p className="text-lg font-bold tabular-nums">
                         {data.stats.averageGlobalScore != null ? (
-                          <ScorePill score={data.stats.averageGlobalScore} />
+                          <ScorePill score={data.stats.averageGlobalScore} precision={2} />
                         ) : '—'}
                       </p>
                       <p className="text-xs text-muted-foreground mt-1">Avg Score</p>