`SquircleView` renders with wrong dimensions inside flex containers

[sherucon]

Environment: react-native-figma-squircle@0.4.0, React Native (New Architecture)

When multiple SquircleView components are placed in a flexDirection: "row" container with flex: 1, the squircle background can render at incorrect dimensions — often appearing visually squashed or mismatched compared to sibling views.

Reproduction:

<View style={{ flexDirection: "row", gap: 8 }}>
  <Pressable style={{ flex: 1, height: 44 }}>
    <SquircleView
      style={StyleSheet.absoluteFill}
      squircleParams={{ cornerSmoothing: 1, cornerRadius: 22, fillColor: "blue" }}
    />
    <Text>Subscribe</Text>
  </Pressable>
  <Pressable style={{ flex: 1, height: 44 }}>
    <SquircleView
      style={StyleSheet.absoluteFill}
      squircleParams={{ cornerSmoothing: 1, cornerRadius: 22, fillColor: "transparent", strokeColor: "gray", strokeWidth: 1 }}
    />
    <Text>Message</Text>
  </Pressable>
</View>

Expected: Both buttons render identically-sized squircle backgrounds.
Actual: The first button's squircle renders at wrong dimensions (often appearing squashed), while the second renders correctly — or vice versa. The behavior is inconsistent across mounts.

Root cause: The internal Rect component (src/index.tsx L143–165) uses useLayoutEffect with an empty dependency array [] and measureInWindow to capture dimensions:

useLayoutEffect(() => {
  ref.current?.measureInWindow((_x, _y, width, height) => {
    setRect({ width, height })
  })
}, [])  // ← never re-runs

This has two problems:

1. Measures once, never updates — if the view's bounds change after mount (screen rotation, flex resolution, dynamic content), the SVG path is permanently stale.
2. Flex timing race — in flex containers, measureInWindow fires during the initial layout pass. When multiple flex siblings are resolving their widths simultaneously, the callback can capture intermediate/pre-resolution dimensions. The SVG path is then computed for a width the view no longer has.