fix: window resize crash by building with Flutter 3.47.7 (v1.6.3)

The GTK embedder's OpenGL compositor uploaded the frame with the window's new
dimensions while its pixel buffer still held the previous size, so memcpy read
past the end of the buffer and the process died with SIGSEGV
(fl_compositor_opengl.cc). Upstream fix: flutter#187626, present in Flutter
3.47.7 but not in 3.44.7.

Linux builds now use /home/alhan/development/flutter-3.47.7; pubspec.lock was
re-resolved for Dart 3.13.5 and the new tool added its build/platform excludes
to analysis_options.yaml. dist/ carries the 1.6.3 package instead of 1.6.2.

CHANGELOG.md

@@ -4,6 +4,15 @@ All notable changes to imajViewer are documented in this file.
 
 ## [Unreleased]
 
+## [1.6.3] - 2026-10-20
+
+### Fixed
+- `SIGSEGV` while resizing the window. The GTK embedder's OpenGL compositor uploaded the frame using
+  the window's new dimensions while its pixel buffer still held the previous size, so `memcpy` read
+  past the end of the buffer (`engine/.../linux/fl_compositor_opengl.cc`). Fixed upstream in
+  flutter#187626, which is not part of Flutter 3.44.7 — the Linux build now uses Flutter 3.47.7,
+  where the compositor derives the texture size from the framebuffer itself.
+
 ## [1.6.2] - 2026-10-14
 
 ### Changed