add steam deploy workflow

.github/workflows/steam.yml

@@ -0,0 +1,57 @@
+name: Deploy to Steam
+
+on:
+  workflow_dispatch:
+    inputs:
+      commit_hash:
+        description: Commit hash
+        type: string
+        required: true
+      version:
+        description: Version
+        type: string
+        required: true
+      release_channel:
+        description: Release channel
+        type: string
+        required: true
+        default: beta
+
+jobs:
+  deploy-to-steam:
+    name: Deploy to Steam
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Clone DFHack
+        uses: actions/checkout@v3
+        with:
+          submodules: true
+          fetch-depth: 0
+          ref: ${{ github.event.inputs.commit_hash }}
+      - name: Fetch ccache
+        uses: actions/cache@v3
+        with:
+          path: build/win64-cross/ccache
+          key: ccache-win64-cross-msvc-${{ github.event.inputs.commit_hash }}
+          restore-keys: |
+            ccache-win64-cross-msvc-${{ github.event.inputs.commit_hash }}
+            ccache-win64-cross-msvc
+      - name: Cross-compile win64 artifacts
+        env:
+          CMAKE_EXTRA_ARGS: '-DBUILD_STONESENSE:BOOL=1'
+        run: |
+          cd build
+          bash -x build-win64-from-linux.sh
+      - name: Steam deploy
+        uses: game-ci/steam-deploy@v2
+        with:
+          username: ${{ secrets.STEAM_USERNAME }}
+          password: ${{ secrets.STEAM_PASSWORD }}
+          configVdf: ${{ secrets.STEAM_CONFIG_VDF}}
+          ssfnFileName: ${{ secrets.STEAM_SSFN_FILE_NAME }}
+          ssfnFileContents: ${{ secrets.STEAM_SSFN_FILE_CONTENTS }}
+          appId: 2346660
+          buildDescription: ${{ github.event.inputs.version }}
+          rootPath: build/win64-cross/output
+          depot1Path: dfhack-windows-x64
+          releaseBranch: ${{ github.event.inputs.release_channel }}