Revert "CI Win: use pre-built Spout"

This reverts commit b300fa6.

we would need to patch the upstream Spout code

Author: MartinPulec

.github/scripts/Windows/install_spout.sh

@@ -1,16 +1,21 @@
 #!/bin/sh -eux
 # Install SPOUT
 
+build() {(
+        cd /c
+        rm -rf Spout2
+        git clone --depth 1 https://github.com/leadedge/Spout2.git
+        cd Spout2
+        /c/Program\ Files/CMake/bin/cmake.exe -Bbuild2 . # ./BUILD already exists
+        /c/Program\ Files/CMake/bin/cmake.exe --build build2 --config Release \
+         -j "$(nproc)"
+)}
+
 install() {(
-        # .github/scripts/download-gh-asset.sh leadedge/Spout2 binaries Spout.zip
-        curl -LSs https://github.com/leadedge/Spout2/releases/download/\
-2.007.016/Spout-SDK-binaries_2-007-016.zip -o Spout.zip
-        unzip Spout.zip
-        # d=$(echo Spout-SDK-binaries/Libs_*)
-        d=$(echo Spout-SDK-binaries/*/Libs)
-        cp "$d"/MT/bin/SpoutLibrary.dll /usr/local/bin/
-        cp "$d"/MT/lib/SpoutLibrary.lib /usr/local/lib/
-        cp "$d"/include/SpoutLibrary/SpoutLibrary.h /usr/local/include/
+        mkdir -p /usr/local/bin /usr/local/include /usr/local/lib
+        cp /c/Spout2/build2/bin/Release/SpoutLibrary.dll /usr/local/bin/
+        cp /c/Spout2/build2/lib/Release/SpoutLibrary.lib /usr/local/lib/
+        cp /c/Spout2/SPOUTSDK/SpoutLibrary/SpoutLibrary.h /usr/local/include/
 )}
 
-install
+$1

.github/workflows/ccpp.yml

@@ -311,8 +311,17 @@ jobs:
     - name: bootsrap MSYS2
       run: $GITHUB_WORKSPACE/.github/scripts/Windows/prepare_msys.sh
 
+    - name: Run actions/cache for Spout build
+      id: cache-spout
+      uses: actions/cache@main
+      with:
+        path: 'C:\Spout2'
+        key: cache-spout-${{ runner.os }}-${{ hashFiles('.github/scripts/Windows/install_spout.sh') }}
+    - name: Build Spout
+      if: steps.cache-spout.outputs.cache-hit != 'true'
+      run: $GITHUB_WORKSPACE/.github/scripts/Windows/install_spout.sh build
     - name: Install Spout
-      run: $GITHUB_WORKSPACE/.github/scripts/Windows/install_spout.sh
+      run: $GITHUB_WORKSPACE/.github/scripts/Windows/install_spout.sh install
 
     - name: Run actions/cache for CineForm build
       id: cache-cineform