feat: show creation time next to pr title

fixtures/github/issues.pull_request.PR_kwDOAgent47.json

@@ -2,6 +2,7 @@
   "title": "feat(prompts): split context loading from execution workers",
   "state": "OPEN",
   "is_draft": true,
+  "created_at": "2026-04-30T14:22:00Z",
   "author": {
     "login": "leaferiksen",
     "avatar_url": "https://avatars.githubusercontent.com/u/5151?v=4"

fixtures/github/issues.pull_request.PR_kwDODesign31.json

@@ -2,6 +2,7 @@
   "title": "chore(tokens): tighten dashboard spacing scale",
   "state": "OPEN",
   "is_draft": false,
+  "created_at": "2026-05-02T11:05:00Z",
   "author": {
     "login": "mariahops",
     "avatar_url": "https://avatars.githubusercontent.com/u/6161?v=4"

fixtures/github/issues.pull_request.PR_kwDOInfra19.json

@@ -2,6 +2,7 @@
   "title": "docs(deploy): document manual failover steps",
   "state": "CLOSED",
   "is_draft": false,
+  "created_at": "2026-04-24T06:40:00Z",
   "author": {
     "login": "kennethnym",
     "avatar_url": "https://avatars.githubusercontent.com/u/4242?v=4"

fixtures/github/issues.pull_request.PR_kwDONovem84.json

@@ -2,6 +2,7 @@
   "title": "feat(dashboard): hydrate issue pane from cached query state",
   "state": "OPEN",
   "is_draft": false,
+  "created_at": "2026-05-01T09:12:00Z",
   "author": {
     "login": "kennethnym",
     "avatar_url": "https://avatars.githubusercontent.com/u/4242?v=4"

fixtures/github/issues.pull_request.PR_kwDONovem85.json

@@ -2,6 +2,7 @@
   "title": "feat(repo): add cached repository query for titlebar picker",
   "state": "OPEN",
   "is_draft": false,
+  "created_at": "2026-05-03T07:40:00Z",
   "author": {
     "login": "kennethnym",
     "avatar_url": "https://avatars.githubusercontent.com/u/4242?v=4"

fixtures/github/issues.pull_request.PR_kwDOSprint62.json

@@ -2,6 +2,7 @@
   "title": "feat(calendar): ship release handoff checklist in weekly planner",
   "state": "MERGED",
   "is_draft": false,
+  "created_at": "2026-04-28T10:20:00Z",
   "author": {
     "login": "rorycraft",
     "avatar_url": "https://avatars.githubusercontent.com/u/7171?v=4"