[Android] Upgrade Android compileSdk and Kotlin version. (#444) [macOS] Robust multi-source drag & drop.

• Prefer public.file-url / legacy filename arrays when present; fall back to NSFilePromiseReceiver (file promises) otherwise.
• Handle directories (isDirectory) and surface as DropItemDirectory.
• Add fromPromise to DropItem so apps can distinguish promise-based drops.
• Generate security-scoped bookmarks only for paths outside the app container (skip/empty for promise files in .../tmp/Drops/...).
• Per-drop unique destination for promised files to avoid name collisions.
• Thread-safe collection of drop results when receiving promises.
• Dart guards: no-op start/stopAccessingSecurityScopedResource on empty bookmarks.
• Bump macOS minimum to 10.13 (SPM/Podspec).

• Fix desktop_drop Linux snap build failure due to missing stdlib.h include (#425)

Migrate macOS to SPM, fix web build.

• https://github.com/MixinNetwork/flutter-plugins/pull/398
• https://github.com/MixinNetwork/flutter-plugins/pull/399
• https://github.com/MixinNetwork/flutter-plugins/pull/403

• upgrade web version to 1.0.0

• fix build on android #285 by AdamVe

• fix windows build warning C4701

• fix crash on Windows when app exit

• [macOS] improve enumerateDraggingItems on macOS.

• [Android] update to later version of kotlin(1.5.2). #155 by Cal Holloway
• [macOS] Fix broken gestures when used with modified MainFlutterWindow. #162 by Josh Matthews

• Fix dragging multiple files at once from Apple Music does not work well. #72

• Fix non ascii characters path on linux. #53

• Fix desktop_drop web lastModifiedDate. (Thanks Luigi Rosso)

** BREAK CHANGES**

• replace DropDoneDetails property urls: List<Uri> to files: List<XFile>. which is more general.

Add web support

[Linux] Fix do not work on Wayland.

update plugin description.

1. add android support. (preview)
2. expose pointer coordinates.

BREAK CHANGE:

1. Change onDragEntered,onDragExited and onDragUpdated callbacks signature from VoidCallback to void Function(DropEventDetails).
2. Change DropDoneDetails from void Function(List<Uri>) to void Function(DropDoneDetails). you can obtain urls by DropDoneDetails.urls.

a file drop plugin for flutter desktop platforms.

• add Linux support.
• add Windows support.
• add macOS support.