[Web] Start hover on the first pointer move when pointerenter was missed (#4624)

## Description

On web, `HoverGestureHandler` begins only on the DOM `pointerenter`
event. The v3 detector attaches its pointer listeners in an effect,
after paint, so when the view mounts under a pointer that is already
resting there, `pointerenter` fires before the listeners exist. The
hover then never begins, even though `pointermove` events keep arriving,
until the pointer leaves the view and enters it again.

`onPointerMove` now begins the hover (through `onPointerMoveOver`) when
the handler is still `UNDETERMINED`, so the first move over the view
starts the gesture.

This was found while migrating Expensify's charts to the hook API in
Expensify/App#103457: the chart tooltip didn't
show when the cursor was already over the chart before it was drawn
([report](Expensify/App#103457 (comment)),
[investigation](Expensify/App#103457 (comment))).

## Test plan

Tested in Expensify/App#103457, where the same
change is applied to `3.3.0` as a
[patch](https://github.com/software-mansion-labs/expensify-app-fork/blob/22686449e25d5f2c6dbe245aca37bdcf515bd9d4/patches/react-native-gesture-handler/react-native-gesture-handler%2B3.3.0%2B001%2Bstart-hover-on-pointer-move.patch):
on web, quickly switching charts in the Insights card while keeping the
cursor over the chart area, the tooltip of the newly drawn chart shows
on the first mouse move, without leaving and re-entering the chart.
Video of the fix is in [this
comment](Expensify/App#103457 (comment)).

---------

Co-authored-by: Michał Bert <63123542+m-bert@users.noreply.github.com>

Author: collectioneur

packages/react-native-gesture-handler/src/web/handlers/HoverGestureHandler.ts

@@ -52,6 +52,12 @@ export default class HoverGestureHandler extends GestureHandler {
     this.tracker.track(event);
     this.stylusData = event.stylusData;
 
+    // `pointerenter` may fire before listeners are attached
+    if (this.state === State.UNDETERMINED) {
+      this.onPointerMoveOver(event);
+      return;
+    }
+
     super.onPointerMove(event);
   }
 }