fix: timestamp auto-updates without triggering fetch on tray open

- Reverted auto-refresh on tray click (fetch only happens on schedule
  or manual Refresh button)
- Timestamp now uses TimelineView(.periodic) to auto-update every 30s:
  'Just now' → '1m ago' → '5m ago' → etc. without any user action

Co-Authored-By: Claude <noreply@anthropic.com>

Sources/AppDelegate.swift

@@ -64,8 +64,6 @@ final class AppDelegate: NSObject, NSApplicationDelegate {
         } else {
             popover.show(relativeTo: button.bounds, of: button, preferredEdge: .minY)
             popover.contentViewController?.view.window?.makeKey()
-            // Refresh on open (PollerService deduplicates if already fetching)
-            Task { await PollerService.shared.fetchNow() }
         }
     }
 

Sources/Views/MenuBar/BugListPopover.swift

@@ -31,9 +31,17 @@ struct BugListPopover: View {
                 Image(systemName: "arrow.triangle.2.circlepath")
                     .font(.caption2)
                     .foregroundStyle(.secondary)
-                Text(bugStore.lastUpdated.map(formatted) ?? "Never")
-                    .font(.caption)
-                    .foregroundStyle(.secondary)
+                if let lastUpdated = bugStore.lastUpdated {
+                    TimelineView(.periodic(from: lastUpdated, by: 30)) { _ in
+                        Text(formatted(lastUpdated))
+                            .font(.caption)
+                            .foregroundStyle(.secondary)
+                    }
+                } else {
+                    Text("Never")
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+                }
             }
             Button("Mark all seen") {
                 bugStore.markAllSeen()