Add automatic retry policy for AI jobs

internal/store/retry_policy.go

@@ -0,0 +1,22 @@
+package store
+
+import (
+	"strings"
+	"time"
+)
+
+type failRetryPolicy struct {
+	Retryable bool
+	Delay     time.Duration
+}
+
+func retryPolicyForError(errorCode string) failRetryPolicy {
+	switch strings.TrimSpace(errorCode) {
+	case "provider_unavailable", "model_unavailable", "timeout", "storage_error", "stale_worker":
+		return failRetryPolicy{Retryable: true, Delay: 30 * time.Second}
+	case "bad_response", "unknown":
+		return failRetryPolicy{Retryable: true, Delay: 2 * time.Minute}
+	default:
+		return failRetryPolicy{}
+	}
+}