fix(ci): graceful tailwind skip and add dx fmt check

build.rs no longer panics when bunx is unavailable, allowing
cargo clippy/test to run in CI without bun installed. Added
dx fmt --check to the format job for RSX formatting validation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -35,6 +35,12 @@ jobs:
           git checkout FETCH_HEAD
       - run: rustup component add rustfmt
       - run: cargo fmt --check
+      - name: Install dx CLI
+        run: |
+          curl -L --proto '=https' --tlsv1.2 -sSf https://raw.githubusercontent.com/cargo-bins/cargo-binstall/main/install-from-binstall-release.sh | bash
+          cargo binstall dioxus-cli@0.7.3 -y --force
+      - name: RSX format check
+        run: dx fmt --check
 
   clippy:
     name: Clippy