fix(android): clean up polyline animator on view drop

[lodev09]

Summary

LuggPolylineView.onDropViewInstance previously only cleared the GMS polyline — it never told GoogleMapProvider to dismantle the matching PolylineAnimator. Cleanup of the polylineAnimators map and ValueAnimator.cancel() lived only in removePolylineView, which is reached via LuggMapView.removeViewAt. If a view instance was dropped without that path firing first (e.g. provider/surface teardown ordering), the entire animator chain leaked: an INFINITE-repeat ValueAnimator is held by the system AnimationHandler, keeping the PolylineAnimator, its coordinates, cumulativeDistances, reusablePoints, and the already-removed Polyline alive across re-mounts.

This PR:

• Adds a polylineViewDidDrop callback to LuggPolylineViewDelegate. LuggPolylineView.onDropViewInstance now notifies the delegate, and GoogleMapProvider routes both removePolylineView and polylineViewDidDrop through a shared teardownPolyline helper.
• Defensively destroys any pre-existing animator entry at the start of addPolylineViewToMap, so a stale registration can't silently overwrite a still-running ValueAnimator.
• Drops the per-frame ArrayList(reusablePoints) wrapper in PolylineAnimator.updateAnimatedPolyline — Polyline.setPoints copies internally, so the wrapping list is unneeded GC churn.

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Test Plan

Stress-tested on Android emulator (Google Maps SDK 20.0.0):

• 100 animated gradient polylines × 500 coords, full batch remounted every 3 s for ~10 minutes (187 generations). Peak `polylineAnimators` size capped at 105 (100 stress + 4 baseline + 1 transient), zero stale-animator warnings, zero "salvage" cleanups via the `didDrop` path. Java heap oscillated 76–121 MB and recovered to ~45 MB on idle.
• 1 animated polyline × 10,000 coords, remounted every 3 s for ~2 minutes. Java heap stable at 41–48 MB, native heap stable at 200–214 MB.

Without this fix, the same scenarios would have leaked a `PolylineAnimator` per remount cycle since `onDropViewInstance` ran without the matching delegate notification. The shared teardown helper makes both paths idempotent.

Checklist

• I tested on iOS
• I tested on Android
• I tested on Web
• I updated the documentation (if needed)