Add TUI kanban board, review workflow, and new task statuses

Replace task statuses (pending/running/succeeded/failed/cancelled) with
a kanban workflow: todo → in_progress → in_review → done/wontdo.

When a non-review agent task completes, the API auto-creates a child
review task and moves the parent to in_review. Only humans can move
tasks from in_review to done/wontdo via the TUI.

New components:
- cmd/tui: bubbletea kanban board with $EDITOR integration
- POST /api/v1/tasks/{id}/complete: agent completion callback
- Operator --api-url flag for completion callbacks
- ProviderQueue sets tasks to in_progress on pickup
- AgentTask reconciler calls /complete on job finish

cmd/operator/main.go

@@ -27,12 +27,18 @@ func main() {
 	var metricsAddr string
 	var probeAddr string
 	var leaderElect bool
+	var apiURL string
 
 	flag.StringVar(&metricsAddr, "metrics-bind-address", ":8080", "metrics endpoint")
 	flag.StringVar(&probeAddr, "health-probe-bind-address", ":8081", "health probe endpoint")
 	flag.BoolVar(&leaderElect, "leader-elect", false, "enable leader election")
+	flag.StringVar(&apiURL, "api-url", "", "forgebot API base URL for task completion callbacks")
 	flag.Parse()
 
+	if v := os.Getenv("FORGEBOT_API_URL"); v != "" && apiURL == "" {
+		apiURL = v
+	}
+
 	ctrl.SetLogger(zap.New(zap.UseDevMode(false)))
 	logger := ctrl.Log.WithName("setup")
 
@@ -50,7 +56,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	if err := controller.SetupAll(mgr); err != nil {
+	if err := controller.SetupAll(mgr, controller.SetupOptions{APIURL: apiURL}); err != nil {
 		logger.Error(err, "unable to setup controllers")
 		os.Exit(1)
 	}