fix: 달력 스와이프 애니메이션 버그 수정

- GestureDetector의 onDown 메서드가 true를 반환하도록 수정

- onInterceptTouchEvent에서 gestureDetector.onTouchEvent(e) 반환값을 리턴하도록 수정

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

app/src/main/java/com/example/shiftalarm/MainActivity.kt

@@ -142,6 +142,10 @@ class MainActivity : AppCompatActivity() {
             private val SWIPE_THRESHOLD = 100
             private val SWIPE_VELOCITY_THRESHOLD = 100
 
+            override fun onDown(e: MotionEvent): Boolean {
+                return true
+            }
+
             override fun onFling(
                 e1: MotionEvent?,
                 e2: MotionEvent,
@@ -171,8 +175,7 @@ class MainActivity : AppCompatActivity() {
 
         binding.calendarGrid.addOnItemTouchListener(object : androidx.recyclerview.widget.RecyclerView.OnItemTouchListener {
             override fun onInterceptTouchEvent(rv: androidx.recyclerview.widget.RecyclerView, e: MotionEvent): Boolean {
-                gestureDetector.onTouchEvent(e)
+                return gestureDetector.onTouchEvent(e)
-                return false
             }
             override fun onTouchEvent(rv: androidx.recyclerview.widget.RecyclerView, e: MotionEvent) {}
             override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) {}