Add Windows cross-build and Gitea release; share CI setup

- just windows-deps / windows / package-windows: cross-compile with Odin
  objects + lld-link against an xwin SDK, static VC runtime
- Release workflow runs on v* tags, builds Linux and Windows packages,
  uploads them to the package registry and creates a Gitea release
- Shared toolchain setup as a local composite action

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitea/actions/setup/action.yaml

@@ -0,0 +1,44 @@
+#
+# .gitea/actions/setup/action.yaml
+#
+# Installs the toolchain shared by all workflows: system packages, Odin and just.
+#
+
+name: "Setup Odin toolchain"
+description: "Install system packages, Odin and just"
+
+inputs:
+  odin-version:
+    description: "Odin release tag (keep in sync with odin_version in the justfile)"
+    default: "dev-2026-09"
+  packages:
+    description: "Extra apt packages to install"
+    default: ""
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install System Packages
+      shell: bash
+      run: |
+        SUDO=""; command -v sudo >/dev/null && SUDO=sudo
+        $SUDO apt-get update
+        # clang links Odin programs on Linux; raylib needs X11
+        $SUDO apt-get install -y --no-install-recommends \
+          clang libx11-dev curl ca-certificates unzip ${{ inputs.packages }}
+
+    - name: Install Odin
+      shell: bash
+      run: |
+        curl -fsSL -o /tmp/odin.tar.gz \
+          https://github.com/odin-lang/Odin/releases/download/${{ inputs.odin-version }}/odin-linux-amd64-${{ inputs.odin-version }}.tar.gz
+        mkdir -p "$HOME/odin"
+        tar -xzf /tmp/odin.tar.gz -C "$HOME/odin" --strip-components=1
+        echo "$HOME/odin" >> "$GITHUB_PATH"
+
+    - name: Install just
+      shell: bash
+      run: |
+        mkdir -p "$HOME/.local/bin"
+        curl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh | bash -s -- --to "$HOME/.local/bin"
+        echo "$HOME/.local/bin" >> "$GITHUB_PATH"

.gitea/workflows/gitea-build.yaml

@@ -1,7 +1,7 @@
 #
 # .gitea/workflows/gitea-build.yaml
 #
-# Builds and tests on every push and pull request to main and develop.
+# Checks, tests and builds on every push and pull request to main and develop.
 #
 
 name: "Build and Test"
@@ -11,9 +11,6 @@ on:
   pull_request:
     branches: [main, develop]
 
-env:
-  ODIN_VERSION: dev-2026-09
-
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -21,25 +18,8 @@ jobs:
       - name: Checkout Repository
         uses: actions/checkout@v4
 
-      - name: Install System Dependencies
-        run: |
-          SUDO=""; command -v sudo >/dev/null && SUDO=sudo
-          $SUDO apt-get update
-          # clang links Odin programs; raylib needs X11 on Linux
-          $SUDO apt-get install -y --no-install-recommends clang libx11-dev curl ca-certificates
-
-      - name: Install Odin
-        run: |
-          curl -fsSL -o odin.tar.gz https://github.com/odin-lang/Odin/releases/download/$ODIN_VERSION/odin-linux-amd64-$ODIN_VERSION.tar.gz
-          mkdir -p "$HOME/odin"
-          tar -xzf odin.tar.gz -C "$HOME/odin" --strip-components=1
-          echo "$HOME/odin" >> "$GITHUB_PATH"
-
-      - name: Install just
-        run: |
-          mkdir -p "$HOME/.local/bin"
-          curl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh | bash -s -- --to "$HOME/.local/bin"
-          echo "$HOME/.local/bin" >> "$GITHUB_PATH"
+      - name: Setup Toolchain
+        uses: ./.gitea/actions/setup
 
       - name: Check
         run: |

.gitea/workflows/gitea-release.yaml

@@ -1,47 +1,33 @@
 #
 # .gitea/workflows/gitea-release.yaml
 #
-# Builds a release package on version branches (e.g. 1.0) and uploads it to
-# the Gitea generic package registry.
+# On a version tag (e.g. v1.0): tests, builds Linux and Windows packages,
+# uploads them to the Gitea generic package registry and creates a Gitea release.
 #
 
-name: "Publish"
+name: "Release"
 on:
   push:
-    branches:
-      - '*.*'
+    tags:
+      - 'v*'
 
 env:
-  ODIN_VERSION: dev-2026-09
   PROJECT_NAME: HanjaKanaMun
-  GAME_VERSION: ${{gitea.ref_name}}
 
 jobs:
-  build:
+  release:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v4
 
-      - name: Install System Dependencies
-        run: |
-          SUDO=""; command -v sudo >/dev/null && SUDO=sudo
-          $SUDO apt-get update
-          # clang links Odin programs; raylib needs X11 on Linux
-          $SUDO apt-get install -y --no-install-recommends clang libx11-dev curl ca-certificates
+      - name: Setup Toolchain
+        uses: ./.gitea/actions/setup
+        with:
+          packages: lld zip
 
-      - name: Install Odin
-        run: |
-          curl -fsSL -o odin.tar.gz https://github.com/odin-lang/Odin/releases/download/$ODIN_VERSION/odin-linux-amd64-$ODIN_VERSION.tar.gz
-          mkdir -p "$HOME/odin"
-          tar -xzf odin.tar.gz -C "$HOME/odin" --strip-components=1
-          echo "$HOME/odin" >> "$GITHUB_PATH"
-
-      - name: Install just
-        run: |
-          mkdir -p "$HOME/.local/bin"
-          curl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh | bash -s -- --to "$HOME/.local/bin"
-          echo "$HOME/.local/bin" >> "$GITHUB_PATH"
+      - name: Set Version
+        run: echo "GAME_VERSION=${GITHUB_REF_NAME#v}" >> "$GITHUB_ENV"
 
       - name: Test
         run: just test
@@ -49,10 +35,30 @@ jobs:
       - name: Linux Build
         run: just package "$GAME_VERSION"
 
-      - name: Upload Artifact Linux
+      - name: Windows Build
+        run: |
+          # Debian/Ubuntu may only ship a versioned lld-link
+          LLD_LINK="$(command -v lld-link || ls /usr/lib/llvm-*/bin/lld-link | sort -V | tail -1)"
+          export LLD_LINK
+          just windows-deps
+          just package-windows "$GAME_VERSION"
+
+      - name: Upload Artifacts
         run: |
           ls -la build
-          FILE="${PROJECT_NAME}_${GAME_VERSION}_linux_x86_64.tar.gz"
-          curl --fail --user ${{ github.repository_owner }}:${{ secrets.TOKEN }} \
-                --upload-file "build/$FILE" \
-                https://gitea.sanplex.xyz/api/packages/sansan/generic/$PROJECT_NAME/$GAME_VERSION/$FILE
+          for FILE in build/${PROJECT_NAME}_${GAME_VERSION}_*; do
+            NAME="$(basename "$FILE")"
+            echo "Uploading $NAME"
+            curl --fail --user ${{ github.repository_owner }}:${{ secrets.TOKEN }} \
+                  --upload-file "$FILE" \
+                  https://gitea.sanplex.xyz/api/packages/sansan/generic/$PROJECT_NAME/$GAME_VERSION/$NAME
+          done
+
+      - name: Create Release
+        uses: akkuman/gitea-release-action@v1
+        env:
+          NODE_OPTIONS: '--experimental-fetch' # if nodejs < 18
+        with:
+          files: |-
+            build/${{ env.PROJECT_NAME }}_*.tar.gz
+            build/${{ env.PROJECT_NAME }}_*.zip