feat(goal-flow): Goal 1줄 앵커와 완료 시트 기반 다음 한 조각 플로우 적용

src/widgets/space-workspace/ui/SpaceWorkspaceWidget.tsx

@@ -182,6 +182,10 @@ export const SpaceWorkspaceWidget = () => {
         goal={goalInput.trim()}
         timerLabel={selectedTimerLabel}
         visible={isFocusMode}
+        onGoalUpdate={(nextGoal) => {
+          setGoalInput(nextGoal);
+          setSelectedGoalId(null);
+        }}
       />
 
       <SpaceToolsDockWidget