feat: add gateway billing estimate and rate limit details

apps/api/internal/runner/limits.go

@@ -52,9 +52,31 @@ func isLocalRateLimitError(err error) bool {
 
 func (s *Service) rateLimitReservations(ctx context.Context, user *auth.User, candidate store.RuntimeModelCandidate, body map[string]any) []store.RateLimitReservation {
 	out := make([]store.RateLimitReservation, 0)
-	out = append(out, reservationsFromPolicy("platform_model", candidate.PlatformModelID, effectiveRateLimitPolicy(candidate), body)...)
+	out = append(out, reservationsFromPolicy(
+		"platform_model",
+		candidate.PlatformModelID,
+		firstNonEmptyString(candidate.DisplayName, candidate.ModelAlias, candidate.ModelName),
+		map[string]any{
+			"platformId":   candidate.PlatformID,
+			"platformName": candidate.PlatformName,
+			"modelAlias":   candidate.ModelAlias,
+			"modelName":    candidate.ModelName,
+		},
+		effectiveRateLimitPolicy(candidate),
+		body,
+	)...)
 	if group, err := s.store.ResolveUserGroupPolicy(ctx, user); err == nil && group.ID != "" {
-		out = append(out, reservationsFromPolicy("user_group", group.ID, group.RateLimitPolicy, body)...)
+		out = append(out, reservationsFromPolicy(
+			"user_group",
+			group.ID,
+			firstNonEmptyString(group.Name, group.GroupKey),
+			map[string]any{
+				"groupKey": group.GroupKey,
+				"name":     group.Name,
+			},
+			group.RateLimitPolicy,
+			body,
+		)...)
 	}
 	return out
 }
@@ -90,7 +112,7 @@ func effectiveRetryPolicy(candidate store.RuntimeModelCandidate) map[string]any
 	return policy
 }
 
-func reservationsFromPolicy(scopeType string, scopeKey string, policy map[string]any, body map[string]any) []store.RateLimitReservation {
+func reservationsFromPolicy(scopeType string, scopeKey string, scopeName string, scopeMetadata map[string]any, policy map[string]any, body map[string]any) []store.RateLimitReservation {
 	if scopeKey == "" || !hasRules(policy) {
 		return nil
 	}
@@ -108,11 +130,14 @@ func reservationsFromPolicy(scopeType string, scopeKey string, policy map[string
 		out = append(out, store.RateLimitReservation{
 			ScopeType:       scopeType,
 			ScopeKey:        scopeKey,
+			ScopeName:       scopeName,
+			ScopeMetadata:   scopeMetadata,
 			Metric:          metric,
 			Limit:           limit,
 			Amount:          amount,
 			WindowSeconds:   int(floatFromAny(rule["windowSeconds"])),
 			LeaseTTLSeconds: int(floatFromAny(rule["leaseTtlSeconds"])),
+			Policy:          policy,
 		})
 	}
 	return out