task: allow requeueing BUDGET_EXCEEDED tasks

Permitted BUDGET_EXCEEDED -> QUEUED transition in ValidTransition. Updated frontend to show 'Restart' button for BUDGET_EXCEEDED tasks, allowing them to be requeued after failure.

3 files changed, 6 insertions, 4 deletions

diff --git a/internal/task/task.go b/internal/task/task.go
index 8bb3214..447c4a3 100644
--- a/internal/task/task.go
+++ b/internal/task/task.go
@@ -121,9 +121,10 @@ func ValidTransition(from, to State) bool {
 		StateRunning:   {StateReady, StateCompleted, StateFailed, StateTimedOut, StateCancelled, StateBudgetExceeded, StateBlocked},
 		StateReady:     {StateCompleted, StatePending},
 		StateFailed:    {StateQueued}, // retry
-		StateTimedOut:  {StateQueued}, // retry
-		StateCancelled: {StateQueued}, // restart
-		StateBlocked:   {StateQueued, StateReady}, // answer received → re-queue as resume execution
+		StateTimedOut:       {StateQueued}, // retry
+		StateCancelled:      {StateQueued}, // restart
+		StateBudgetExceeded: {StateQueued}, // retry
+		StateBlocked:        {StateQueued, StateReady}, // answer received → re-queue as resume execution
 	}
 	for _, allowed := range transitions[from] {
 		if allowed == to {
diff --git a/internal/task/task_test.go b/internal/task/task_test.go
index 5cb12d0..637baf5 100644
--- a/internal/task/task_test.go
+++ b/internal/task/task_test.go
@@ -25,6 +25,7 @@ func TestValidTransition_AllowedTransitions(t *testing.T) {
 		{"running to blocked (question)", StateRunning, StateBlocked},
 		{"blocked to queued (answer resume)", StateBlocked, StateQueued},
 		{"blocked to ready (parent unblocked by subtasks)", StateBlocked, StateReady},
+		{"budget exceeded to queued (retry)", StateBudgetExceeded, StateQueued},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
diff --git a/web/app.js b/web/app.js
index 9742c25..adaa0a2 100644
--- a/web/app.js
+++ b/web/app.js
@@ -125,7 +125,7 @@ function createTaskCard(task) {
   }
 
   // Footer: action buttons based on state
-  const RESTART_STATES = new Set(['FAILED', 'CANCELLED']);
+  const RESTART_STATES = new Set(['FAILED', 'CANCELLED', 'BUDGET_EXCEEDED']);
   if (task.state === 'PENDING' || task.state === 'RUNNING' || task.state === 'READY' || task.state === 'BLOCKED' || task.state === 'TIMED_OUT' || RESTART_STATES.has(task.state)) {
     const footer = document.createElement('div');
     footer.className = 'task-card-footer';