feat(PBI-61): filter popover + created_at op job-kaart (#158)

- Nieuwe JobsColumn met Kind/Status filter-popover per kolom (Actief/Klaar)
- Filterstate persistent in localStorage (whitelist-validatie tegen corrupte waardes)
- Active-filter badges in kolomheader, klikbaar om te wissen
- Aanmaakdatum + tijd rechtsonder op elke JobCard (nl-NL short formaat)

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

components/jobs/job-card.tsx

@@ -19,6 +19,7 @@ interface JobCardProps {
   branch?: string | null
   error?: string | null
   summary?: string | null
+  createdAt: Date | string
   isSelected?: boolean
   onClick?: () => void
 }
@@ -33,7 +34,7 @@ const KIND_LABELS: Record<ClaudeJobKind, string> = {
 
 export default function JobCard({
   kind, status, taskCode, taskTitle, ideaCode, ideaTitle,
-  sprintGoal, sprintCode, productName, branch, error, isSelected, onClick,
+  sprintGoal, sprintCode, productName, branch, error, createdAt, isSelected, onClick,
 }: JobCardProps) {
   let titleText: string
   if (kind === 'TASK_IMPLEMENTATION') {
@@ -70,7 +71,12 @@ export default function JobCard({
         </span>
       </div>
       <p className="font-medium truncate mt-1">{titleText}</p>
-      <p className="text-xs text-muted-foreground truncate mt-0.5">{detailText}</p>
+      <div className="flex items-end justify-between gap-2 mt-0.5">
+        <p className="text-xs text-muted-foreground truncate">{detailText}</p>
+        <span className="text-[10px] text-muted-foreground shrink-0 tabular-nums">
+          {new Date(createdAt).toLocaleString('nl-NL', { dateStyle: 'short', timeStyle: 'short' })}
+        </span>
+      </div>
     </div>
   )
 }