ci: use the shared SDK specification action

Author: ariesclark

.github/workflows/build.yaml

@@ -3,20 +3,41 @@ on:
     branches:
       - '**'
   pull_request:
-  workflow_dispatch:
+  workflow_call:
+    inputs:
+      spec-artifact:
+        description: >-
+          Artifact holding the bundled specification. Only reachable when the
+          caller shares this run; when empty the latest published one is used.
+        required: false
+        type: string
+        default: ''
+      ref:
+        description: Ref of this repository to build.
+        required: false
+        type: string
+        default: main
 
 name: Build
 
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: vrchatapi/specification/.github/actions/sdk-spec@ci/modernise-actions
+        with:
+          repository: vrchatapi/vrchatapi-python
+          ref: ${{ inputs.ref || github.ref }}
+          generator-version: 6.2.1
+          spec-artifact: ${{ inputs.spec-artifact }}
 
       - uses: actions/setup-python@v7
         with:
           python-version: '3.14'
 
+      # generate.sh stamps the version into setup.py, so it comes from the spec.
+      - run: bash ./generate.sh openapi.json "$(jq -r '.info.version' openapi.json)"
+
       - run: python -m pip install --upgrade pip build
 
       - run: python -m build