feat: add review status icon and merge status indicator to PR list rows

Add per-PR review state aggregation by fetching reviews concurrently
via the existing semaphore pattern. Display review status (approved,
changes requested, awaiting) and merge status (ready/conflicts) as
compact badges in each PR card row.

- Add ReviewState field to PullRequest struct
- Add GetPullReviewState() and EnrichPullsWithReviewState() to client
- Call enrichment in ListPulls handler after fetching PRs
- Update pulls template with review and merge badges
- Add CSS for .review-badge and .merge-badge classes

Closes leeworks-agents/gitea-mobile#97

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

static/style.css

@@ -419,6 +419,29 @@ a:active {
   vertical-align: middle;
 }
 
+/* Review status badges */
+.review-badge {
+  font-size: 0.7rem;
+  font-weight: 600;
+  padding: 1px 4px;
+  border-radius: var(--radius-pill);
+  vertical-align: middle;
+}
+.review-approved { color: var(--accent-green); }
+.review-changes { color: var(--accent-red); }
+.review-pending { color: var(--accent-yellow); }
+
+/* Merge status badges */
+.merge-badge {
+  font-size: 0.65rem;
+  font-weight: 600;
+  padding: 1px 5px;
+  border-radius: var(--radius-pill);
+  vertical-align: middle;
+}
+.merge-ready { color: var(--accent-green); border: 1px solid var(--accent-green); }
+.merge-conflicts { color: var(--accent-red); border: 1px solid var(--accent-red); }
+
 /* Empty state */
 .empty {
   text-align: center;