fix(ci): force cargo-binstall to install tarpaulin binary

Stale metadata in ~/.cargo/.crates.toml on the Mac Mini runner caused
binstall to skip installation, reporting "already installed" while the
binary only existed at the mise shims path. Adding --force ensures the
binary is always placed in ~/.cargo/bin/ where cargo can find it.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: pythoninthegrass

.github/workflows/test.yml

@@ -210,7 +210,7 @@ jobs:
       - uses: cargo-bins/cargo-binstall@main
 
       - name: Install cargo-tarpaulin
-        run: cargo binstall --no-confirm cargo-tarpaulin
+        run: cargo binstall --no-confirm --force cargo-tarpaulin
 
       - name: Run Rust tests with coverage
         run: |