Tentative Github action.

.github/workflows/build.yml

@@ -0,0 +1,63 @@
+name: Build USVFS
+
+on:
+  push:
+    branches: master
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+env:
+  BOOST_PREBUILT_URL: "https://github.com/ModOrganizer2/mob/releases/download/2.5-dependencies/boost_prebuilt_1_85_0.7z"
+
+jobs:
+  build-x64:
+    name: Build USVFS x64
+    runs-on: windows-2022
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - name: Fetch Boost prebuilt
+        run: |
+          Invoke-WebRequest -Uri ${env:BOOST_PREBUILT_URL} -OutFile boost.7z
+          Expand-7ZipArchive -Path boost.7z -Destination .\boost
+      - name: Add msbuild to PATH
+        uses: microsoft/setup-msbuild@v2
+      - name: Build x64
+        run: |
+          msbuild -nologo `
+            -maxCpuCount "-property:UseMultiToolTask=true" "-property:EnforceProcessCountAcrossBuilds=true" `
+            "-property:Configuration=Release" `
+            "-property:PlatformToolset=v143" `
+            "-property:WindowsTargetPlatformVersion=10.0.22621.0" `
+            "-property:Platform=x64" `
+            "-property:BOOST_PATH=..\boost" `
+            "-property:RunCodeAnalysis=false" `
+            .\vsbuild\usvfs.sln
+
+  build-x86:
+    name: Build USVFS x86
+    runs-on: windows-2022
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - name: Fetch Boost prebuilt
+        run: |
+          Invoke-WebRequest -Uri ${env:BOOST_PREBUILT_URL} -OutFile boost.7z
+          Expand-7ZipArchive -Path boost.7z -Destination .\boost
+      - name: Add msbuild to PATH
+        uses: microsoft/setup-msbuild@v2
+        with:
+          msbuild-architecture: x86
+      - name: Build x86
+        run: |
+          msbuild -nologo `
+            -maxCpuCount "-property:UseMultiToolTask=true" "-property:EnforceProcessCountAcrossBuilds=true" `
+            "-property:Configuration=Release" `
+            "-property:PlatformToolset=v143" `
+            "-property:WindowsTargetPlatformVersion=10.0.22621.0" `
+            "-property:Platform=x86" `
+            "-property:BOOST_PATH=..\boost" `
+            "-property:RunCodeAnalysis=false" `
+            .\vsbuild\usvfs.sln