fix!: migrate pan gesture to Gesture Handler 3

[marqroldan]

Summary

• Replace the Gesture Handler 2 Gesture.Pan() builder with Gesture Handler 3's usePanGesture hook.
• Preserve the drag lifecycle by mapping onBegin and onUpdate directly and mapping onEnd to onDeactivate.
• Keep the snap worklet stable with useCallback and resolve the existing effect-dependency lint errors.
• Require Gesture Handler 3 in the development and peer dependency ranges, document the compatibility boundary, and add a regression test.
• Align the example app with Gesture Handler 3 and repair the repository's Yarn/TypeScript declarations so CI can install and typecheck reproducibly.

Why

Gesture Handler 3 routes builder gestures through its legacy detector bridge. In a Reanimated UI runtime that bridge can serialize an undefined state-manager module namespace and crash with:

Cannot read property 'GestureStateManager' of undefined

Using the v3 hook API avoids that legacy path entirely.

Fixes #2.

Breaking change

react-native-gesture-handler 3 or newer is now required. Gesture Handler 2 consumers should remain on react-native-snap-area@0.1.x, so this should be released as a compatibility-breaking version.

Verification

• yarn install --cwd example --frozen-lockfile
• yarn install --frozen-lockfile
• yarn lint (passes with existing inline-style warnings)
• yarn typecheck
• yarn test --runInBand
• yarn prepack
• npm pack --dry-run
• Verified generated CommonJS and ESM output use usePanGesture and contain no Gesture.Pan() call.
• Verified the same migration in a downstream Expo Android production export.