Implement linux export test as CI GitHub action

.github/workflows/linux_export.yml

@@ -0,0 +1,35 @@
+name: Linux Export Test
+
+on: [push]
+
+env:
+  CARGO_TERM_COLOR: always
+  RUSTFLAGS: -Dwarnings
+  CARGO_INCREMENTAL: 0
+
+jobs:
+  rust-build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: rui314/setup-mold@v1
+      - uses: chickensoft-games/setup-godot@v1
+        name: 🤖 Setup Godot
+        with:
+          version: 4.2.1
+          include-templates: true
+      - name: Build
+        run: cd rust; cargo build --release
+
+      - name: Godot Check
+        run: |
+          godot --version
+        
+      - name: Godot Export
+        run: |
+          cd godot
+          godot --headless --export-debug "Linux/X11" "../export/linux/Godot Spike.x86_64"
+          if [ ! -f "../export/linux/Godot Spike" ]; then
+            echo "Exported file not found"
+            exit 1
+          fi