feat: weighted criteria in AI ranking, z-score normalization, threshold advancement, CSV export

- Add criteriaWeights to EvaluationConfig for per-criterion weight assignment (0-10)
- Rewrite ai-ranking service: fetch eval form criteria, compute per-criterion averages,
  z-score normalize juror scores to correct grading bias, send weighted criteria to AI
- Update AI prompts with criteria_definitions and per-project criteria_scores
- compositeScore uses weighted criteria when configured, falls back to globalScore
- Add collapsible ranking config section to dashboard (criteria text + weight sliders)
- Move rankingCriteria textarea from eval config tab to ranking dashboard
- Store criteriaWeights in ranking snapshot parsedRulesJson for audit
- Enhance projectScores CSV export with per-criterion averages, category, country
- Add Export CSV button to ranking dashboard header
- Add threshold-based advancement mode (decimal score threshold, e.g. 6.5)
  alongside existing top-N mode in advance dialog

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

src/server/routers/ranking.ts

@@ -85,7 +85,16 @@ export const rankingRouter = router({
         fetchAndRankCategory('BUSINESS_CONCEPT', rules, input.roundId, ctx.prisma, ctx.user.id),
       ])
 
-      // Persist snapshot
+      // Read criteria weights for snapshot audit trail
+      const round = await ctx.prisma.round.findUniqueOrThrow({
+        where: { id: input.roundId },
+        select: { configJson: true },
+      })
+      const evalConfig = (round.configJson as EvaluationConfig | null) ?? ({} as EvaluationConfig)
+      const criteriaWeights = evalConfig.criteriaWeights ?? undefined
+
+      // Persist snapshot — embed weights alongside rules for audit
+      const parsedRulesWithWeights = { rules, weights: criteriaWeights } as unknown as Prisma.InputJsonValue
       const snapshot = await ctx.prisma.rankingSnapshot.create({
         data: {
           roundId: input.roundId,
@@ -94,7 +103,7 @@ export const rankingRouter = router({
           mode: 'CONFIRMED',
           status: 'COMPLETED',
           criteriaText: input.criteriaText,
-          parsedRulesJson: rules as unknown as Prisma.InputJsonValue,
+          parsedRulesJson: parsedRulesWithWeights,
           startupRankingJson: startup.rankedProjects as unknown as Prisma.InputJsonValue,
           conceptRankingJson: concept.rankedProjects as unknown as Prisma.InputJsonValue,
         },
@@ -271,13 +280,16 @@ export const rankingRouter = router({
 
       const result = await aiQuickRank(criteriaText, roundId, ctx.prisma, ctx.user.id)
 
+      // Embed weights alongside rules for audit
+      const criteriaWeights = config.criteriaWeights ?? undefined
+      const parsedRulesWithWeights = { rules: result.parsedRules, weights: criteriaWeights } as unknown as Prisma.InputJsonValue
       const snapshot = await ctx.prisma.rankingSnapshot.create({
         data: {
           roundId,
           triggeredById: ctx.user.id,
           triggerType: 'MANUAL',
           criteriaText,
-          parsedRulesJson: result.parsedRules as unknown as Prisma.InputJsonValue,
+          parsedRulesJson: parsedRulesWithWeights,
           startupRankingJson: result.startup.rankedProjects as unknown as Prisma.InputJsonValue,
           conceptRankingJson: result.concept.rankedProjects as unknown as Prisma.InputJsonValue,
           mode: 'QUICK',