[Bug] Scrolling when selecting on IOS

### Bug Description

The IOS version of AppFlowy tends to scroll whenever I select text, making me select a bunch of text I didn’t want selected.

### How to Reproduce

Select text in a document.
Attempt to move the bars on either side of the selection.

### Expected Behavior

I expected the selection to simply expand to wherever I moved the bars to, so I can easily bolden or italicize pre-written text.

### Operating System

26.5

### AppFlowy Version(s)

0.13.0

### Screenshots

_No response_

### Additional Context

_No response_

Reproduce the selection-handle behavior on iOS 26.5 with AppFlowy 0.13.0, then trace the Flutter text-selection handling used by document editing. Done means dragging either selection handle expands the selection without unintended scrolling, so the selected text matches the handle position.

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