ci: Add GitHub Actions workflow for static checks

Author: Wasim

.github/workflows/ci.yml

@@ -0,0 +1,56 @@
+name: CI
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  static-checks:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    
+    - name: Use Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '20'
+
+    - name: Syntax check for shell scripts
+      run: |
+        while IFS= read -r file; do bash -n "$file"; done < <(
+          find . -type f \( -name '*.sh' -o -name '*.command' \) \
+            ! -path '*/release/*' -print
+        )
+
+    - name: Syntax check for Node.js scripts
+      run: |
+        while IFS= read -r file; do node --check "$file" >/dev/null; done < <(
+          find . -type f \( -name '*.mjs' -o -name '*.js' \) -print
+        )
+
+    - name: Grep assertions (Legacy identifiers)
+      run: |
+        if grep -R -n -E 'dream-skin-skin|DREAM_SKIN_SKIN|1\.0\.0-rc2' ./macos/scripts ./assets >/dev/null 2>&1; then
+          printf 'Legacy release-candidate identifiers remain in runtime files.\n' >&2
+          exit 1
+        fi
+
+    - name: Grep assertions (app.asar mutation)
+      run: |
+        if grep -R -n -E '(writeFile|rename|copyFile|rm).*app\.asar' ./macos/scripts >/dev/null 2>&1; then
+          printf 'A runtime script appears to mutate app.asar.\n' >&2
+          exit 1
+        fi
+
+    - name: Grep assertions (python3 / eval in common-macos.sh)
+      run: |
+        if grep -n -E '/usr/bin/python3|(^|[[:space:]])eval([[:space:]]|$)' ./macos/scripts/common-macos.sh >/dev/null 2>&1; then
+          printf 'The shared macOS runtime must parse state with the bundled Node.js, without python3 or eval.\n' >&2
+          exit 1
+        fi
+
+    - name: Version consistency and HOME recovery assertion
+      run: |
+        /usr/bin/env -u HOME bash -c '. "$1/macos/scripts/common-macos.sh"; [ -n "$HOME" ] && [ "$SKIN_VERSION" = "$(cat "$1/VERSION" 2>/dev/null | tr -d '\''\n\r'\'')" ]' _ "."