Update FLTK in the AppImage (LMMS#7710)

Bump fltk 1.3.x->1.4.1
Closes LMMS#5386

Author: tresf

.github/workflows/build.yml

@@ -25,6 +25,13 @@ jobs:
         with:
           fetch-depth: 0
           submodules: recursive
+      - name: Clone fltk
+        uses: actions/checkout@v4
+        with:
+          repository: fltk/fltk
+          path: fltk
+          ref: 27d991f046bdebb12bfd58f7c05a19f135979c29
+          fetch-depth: 1
       - name: Configure winehq
         run: |
           sudo dpkg --add-architecture i386
@@ -37,8 +44,10 @@ jobs:
         run: |
           sudo apt-get update -y
           sudo apt-get install -y --no-install-recommends \
-          $(xargs < .github/workflows/deps-ubuntu-24.04-gcc.txt)
+            $(xargs < .github/workflows/deps-ubuntu-24.04-gcc.txt)
           sudo apt-get install -y --install-recommends g++-multilib gcc-multilib winehq-stable wine-stable-dev
+          sudo apt-get install -y --install-recommends \
+            $(xargs < .github/workflows/deps-ubuntu-24.04-fltk.txt)
       - name: Cache ccache data
         uses: actions/cache@v3
         with:
@@ -47,6 +56,14 @@ jobs:
             ccache-${{ github.job }}-${{ github.ref }}-
             ccache-${{ github.job }}-
           path: ~/.ccache
+      - name: Configure fltk
+        run: |
+          cmake -S fltk -B fltk/build -DFLTK_BUILD_SHARED_LIBS=ON -DFLTK_BACKEND_WAYLAND=ON \
+            -DFLTK_USE_LIBDECOR_GTK=OFF -DFLTK_BUILD_TEST=OFF -DFLTK_BUILD_GL=OFF
+      - name: Install fltk
+        run: |
+          cmake --build fltk/build
+          sudo cmake --install fltk/build --prefix /usr
       - name: Configure
         run: |
           ccache --zero-stats
@@ -98,11 +115,20 @@ jobs:
         with:
           fetch-depth: 0
           submodules: recursive
+      - name: Clone fltk
+        uses: actions/checkout@v4
+        with:
+          repository: fltk/fltk
+          path: fltk
+          ref: 27d991f046bdebb12bfd58f7c05a19f135979c29
+          fetch-depth: 1
       - name: Install system packages
         run: |
           sudo apt-get update -y
           sudo apt-get install -y --no-install-recommends \
             $(xargs < .github/workflows/deps-ubuntu-24.04-gcc.txt)
+          sudo apt-get install -y --install-recommends \
+            $(xargs < .github/workflows/deps-ubuntu-24.04-fltk.txt)
       - name: Cache ccache data
         uses: actions/cache@v3
         with:
@@ -111,6 +137,14 @@ jobs:
             ccache-${{ github.job }}-${{ github.ref }}-
             ccache-${{ github.job }}-
           path: ~/.ccache
+      - name: Configure fltk
+        run: |
+          cmake -S fltk -B fltk/build -DFLTK_BUILD_SHARED_LIBS=ON -DFLTK_BACKEND_WAYLAND=ON \
+            -DFLTK_USE_LIBDECOR_GTK=OFF -DFLTK_BUILD_TEST=OFF -DFLTK_BUILD_GL=OFF
+      - name: Install fltk
+        run: |
+          cmake --build fltk/build
+          sudo cmake --install fltk/build --prefix /usr
       - name: Configure
         run: |
           ccache --zero-stats

.github/workflows/deps-ubuntu-24.04-fltk.txt

@@ -0,0 +1,3 @@
+libcairo2-dev
+libpango1.0-dev
+wayland-protocols

.github/workflows/deps-ubuntu-24.04-gcc.txt

@@ -11,7 +11,6 @@ g++
 libasound2-dev
 libc6-dev
 libfftw3-dev
-libfltk1.3-dev
 libfluidsynth-dev
 libgig-dev
 libgtk2.0-0