perf: narrow optimization_features select in getTraceData, fix pre-existing type errors

- optimization_features.findFirst: select only 12 consumed fields instead
  of all 30+ columns (skips optimizations_raw, speedup_ratio,
  experiment_metadata, original_runtime, approval_*, slack_message_ts, etc.)
- optimization_errors.findMany: add id and created_at back to select
  (fixes 5 pre-existing TS2339 errors in page.tsx, trace page, and
  llm-export route that accessed these fields on narrowed types)

js/cf-webapp/src/app/observability/lib/get-trace-data.ts

@@ -26,14 +26,30 @@ export async function getTraceData(tracePrefix: string) {
       where: { trace_id: { startsWith: tracePrefix } },
       orderBy: { created_at: "asc" },
       select: {
+        id: true,
         error_type: true,
         severity: true,
         error_message: true,
         context: true,
+        created_at: true,
       },
     }),
     prisma.optimization_features.findFirst({
       where: { trace_id: { startsWith: tracePrefix } },
+      select: {
+        original_code: true,
+        optimizations_post: true,
+        explanations_post: true,
+        optimizations_origin: true,
+        ranking: true,
+        pull_request: true,
+        metadata: true,
+        test_framework: true,
+        generated_test: true,
+        instrumented_generated_test: true,
+        instrumented_perf_test: true,
+        dependency_code: true,
+      },
     }),
     prisma.optimization_events.findFirst({
       where: { trace_id: { startsWith: tracePrefix } },