v1.3.0

What's Changed

• breaking change: local build. Will download opencv sdk (~100M) from remote, set DARTCV_CACHE_DIR to cache it and avoid downloading in every build.
• breaking change: many async class constructors and getters/setters were removed.
• Breaking change: highgui, remove Window and Trackbar class, use functions like opencv c++ and python directly, e.g., cv.namedWindow("TestWindow"), more examples refer to: https://github.com/rainyl/opencv_dart/blob/main/packages/dartcv/test/highgui_test.dart
• macos: support 10.15 and above
• android: API level 24 and above
• ios: 12.0 and above
• support custom linked ffmpeg 6.1 for windows, linux, android, macos
• add DartCvMacOS dependency for macos
• add DartCvIOS for ios
• move all dart code to independent plugin dartcv4
• bump dartcv to 1.0.1
• add cv.Mat.fromMat
• update examples by @rainyl in #260
• fix change log styling by @abdelaziz-mahdy in #261
• Support local build, support ffmpeg for windows, linux, macos, android by @rainyl in #262
• fix formatter, coveragee by @rainyl in #269
• Docs and more tests by @rainyl in #270
• update readme by @rainyl in #271 #272 #273
• more tests, bump opencv_core and opencv_dart to 1.3.0 by @rainyl in #274

Full Changelog: v1.2.5...v1.3.0