fix(modal): consider scrollable content while dragging when expandToScroll is false (#30257)

Issue number: internal

---------
## What is the current behavior?
Changes introduced by #30235 caused two major issues:
- Animations were not being played when increasing breakpoints.
- When the scrollable content was at the top, and a big scroll to the
bottom of the list was made, the modal would jump to a higher
breakpoint.

## What is the new behavior?
- When `expandToScroll` is false, the swipe gesture is allowed unless
it's a pull down within scrollable content.
- When `expandToScroll` is false, we cancel the `moveSheetToBreakpoint`
when a scroll to top is being done within the scrollable content

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

## Other information
| Before | After |
|--------|-------|
| <video
src="https://github.com/user-attachments/assets/e1c22f48-f990-45cf-a6c4-1aec0d019c6d">
| <video
src="https://github.com/user-attachments/assets/f01e0480-748f-40af-ac11-94f790f0e197">
|

core/src/components/modal/gestures/sheet.ts

@@ -264,12 +264,17 @@ export const createSheetGesture = (
 
   const onMove = (detail: GestureDetail) => {
     /**
-     * If `expandToScroll` is disabled, we should not allow the swipe gesture
-     * to continue if the gesture is not pulling down.
+     * If `expandToScroll` is disabled, and an upwards swipe gesture is done within
+     * the scrollable content, we should not allow the swipe gesture to continue.
      */
     if (!expandToScroll && detail.deltaY <= 0) {
+      const contentEl = findClosestIonContent(detail.event.target! as HTMLElement);
+      const scrollEl =
+        contentEl && isIonContent(contentEl) ? getElementRoot(contentEl).querySelector('.inner-scroll') : contentEl;
+      if (scrollEl) {
         return;
       }
+    }
 
     /**
      * If we are pulling down, then it is possible we are pulling on the content.
@@ -324,6 +329,19 @@ export const createSheetGesture = (
   };
 
   const onEnd = (detail: GestureDetail) => {
+    /**
+     * If expandToScroll is disabled, we should not allow the moveSheetToBreakpoint
+     * function to be called if the user is trying to swipe content upwards and the content
+     * is not scrolled to the top.
+     */
+    if (!expandToScroll && detail.deltaY <= 0 && findClosestIonContent(detail.event.target! as HTMLElement)) {
+      const contentEl = findClosestIonContent(detail.event.target! as HTMLElement)!;
+      const scrollEl = isIonContent(contentEl) ? getElementRoot(contentEl).querySelector('.inner-scroll') : contentEl;
+      if (scrollEl!.scrollTop > 0) {
+        return;
+      }
+    }
+
     /**
      * When the gesture releases, we need to determine
      * the closest breakpoint to snap to.