refactor(desktop-task): extract recovery select query and scan task status

Pull the recovered-task SELECT into a dedicated helper so the column list and
lease-expiry filter are testable, add a status column to the scan so logs
report the real task state, and log scan/iterate failures with the client and
recovery mode for observability.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/internal/tenant/app/desktop_task_service.go

@@ -1363,27 +1363,8 @@ func (s *DesktopTaskService) recoverClientTasks(
 	defer tx.Rollback(ctx)
 
 	repo := repository.NewDesktopTaskRepository(tx)
-	query := `
+	query := desktopTaskRecoverySelectQuery(mode)
-		SELECT
-			desktop_id,
-			workspace_id,
-			kind,
-			active_attempt_id
-		FROM desktop_tasks
-		WHERE target_client_id = $1
-		  AND workspace_id = $2
-		  AND status = 'in_progress'
-	`
 	queryArgs := []any{client.ID, client.WorkspaceID}
-	if mode == desktopTaskRecoveryModeLeaseExpiry {
-		query += `
-		  AND lease_expires_at IS NOT NULL
-		  AND lease_expires_at < NOW()
-		`
-	}
-	query += `
-		FOR UPDATE
-	`
 
 	rows, err := tx.Query(ctx, query, queryArgs...)
 	if err != nil {
@@ -1402,11 +1383,13 @@ func (s *DesktopTaskService) recoverClientTasks(
 			&item.Status,
 			&item.ActiveAttempt,
 		); scanErr != nil {
+			s.logWarn("desktop task recovery scan failed", scanErr, zap.String("client_id", client.ID.String()), zap.String("mode", string(mode)))
 			return response.ErrInternal(50198, "desktop_task_recovery_scan_failed", "failed to parse recovered desktop tasks")
 		}
 		recovered = append(recovered, item)
 	}
 	if err := rows.Err(); err != nil {
+		s.logWarn("desktop task recovery rows failed", err, zap.String("client_id", client.ID.String()), zap.String("mode", string(mode)))
 		return response.ErrInternal(50198, "desktop_task_recovery_scan_failed", "failed to iterate recovered desktop tasks")
 	}
 
@@ -1509,6 +1492,31 @@ func (s *DesktopTaskService) recoverClientTasks(
 	return nil
 }
 
+func desktopTaskRecoverySelectQuery(mode desktopTaskRecoveryMode) string {
+	query := `
+		SELECT
+			desktop_id,
+			workspace_id,
+			kind,
+			status,
+			active_attempt_id
+		FROM desktop_tasks
+		WHERE target_client_id = $1
+		  AND workspace_id = $2
+		  AND status = 'in_progress'
+	`
+	if mode == desktopTaskRecoveryModeLeaseExpiry {
+		query += `
+		  AND lease_expires_at IS NOT NULL
+		  AND lease_expires_at < NOW()
+		`
+	}
+	query += `
+		FOR UPDATE
+	`
+	return query
+}
+
 func desktopTaskRecoveryPayload(mode desktopTaskRecoveryMode, kind string) ([]byte, string, string, error) {
 	reason := strings.TrimSpace(string(mode))
 	message := "desktop task was recovered after the client lost the active lease"

server/internal/tenant/app/desktop_task_service_test.go

@@ -0,0 +1,63 @@
+package app
+
+import (
+	"regexp"
+	"strings"
+	"testing"
+)
+
+func TestDesktopTaskRecoverySelectQueryMatchesRecoveredLeaseScanOrder(t *testing.T) {
+	t.Parallel()
+
+	query := desktopTaskRecoverySelectQuery(desktopTaskRecoveryModeStartup)
+	gotColumns := recoverDesktopTaskSelectColumns(query)
+	wantColumns := []string{
+		"desktop_id",
+		"workspace_id",
+		"kind",
+		"status",
+		"active_attempt_id",
+	}
+
+	if len(gotColumns) != len(wantColumns) {
+		t.Fatalf("recover select columns = %v, want %v", gotColumns, wantColumns)
+	}
+	for index := range wantColumns {
+		if gotColumns[index] != wantColumns[index] {
+			t.Fatalf("recover select columns = %v, want %v", gotColumns, wantColumns)
+		}
+	}
+}
+
+func TestDesktopTaskRecoverySelectQueryLeaseExpiryFiltersExpiredLeases(t *testing.T) {
+	t.Parallel()
+
+	query := desktopTaskRecoverySelectQuery(desktopTaskRecoveryModeLeaseExpiry)
+
+	for _, fragment := range []string{
+		"AND lease_expires_at IS NOT NULL",
+		"AND lease_expires_at < NOW()",
+		"FOR UPDATE",
+	} {
+		if !strings.Contains(query, fragment) {
+			t.Fatalf("recover lease-expiry query missing %q: %s", fragment, query)
+		}
+	}
+}
+
+func recoverDesktopTaskSelectColumns(query string) []string {
+	re := regexp.MustCompile(`(?is)select\s+(.*?)\s+from\s+desktop_tasks`)
+	match := re.FindStringSubmatch(query)
+	if len(match) != 2 {
+		return nil
+	}
+
+	rawColumns := strings.Split(match[1], ",")
+	columns := make([]string, 0, len(rawColumns))
+	for _, rawColumn := range rawColumns {
+		column := strings.TrimSpace(rawColumn)
+		column = strings.Fields(column)[0]
+		columns = append(columns, column)
+	}
+	return columns
+}