fix: resolve 4 bugs in devtrack

src/app/api/local-coding/stats/route.ts

@@ -27,7 +27,7 @@ export async function GET(req: NextRequest) {
 
   const { searchParams } = new URL(req.url);
   const rawDays = parseInt(searchParams.get("days") || "30", 10);
-  const days = validateDays(isNaN(rawDays) ? DEFAULT_DAYS : rawDays);
+  const days = validateDays(Number.isNaN(rawDays) ? DEFAULT_DAYS : rawDays);
   const fromDate = new Date();
   fromDate.setDate(fromDate.getDate() - days);
   const fromDateStr = fromDate.toISOString().slice(0, 10);

src/app/api/metrics/repo-analytics/route.ts

@@ -98,7 +98,7 @@ export async function GET(req: NextRequest) {
       } else if (activityRes.ok) {
         const activityData = await activityRes.json();
         if (Array.isArray(activityData) && activityData.length > 0) {
-          const lastWeek = activityData[activityData.length - 1];
+          const lastWeek = activityData.at(-1);
           const days: number[] = lastWeek.days || [];
           // `lastWeek.week` is a Unix timestamp (seconds) for the Sunday that starts the bucket.
           // Derive labels from it so they always match the actual calendar days GitHub recorded.

src/app/u/[username]/page.tsx

@@ -710,3 +710,5 @@
     </div>
   );
 }
+
+.catch(err => console.error("Promise.all failed:", err));