chore(ci): replace artifact upload with binary verification

Remove the upload-artifact step in the CI workflow and add verification
steps to run the binary with --help and list its details.

.gitea/workflows/ci.yml

@@ -74,8 +74,7 @@ jobs:
       - name: Build
         run: make build
 
-      - name: Upload artifacts
-        uses: actions/upload-artifact@v4
-        with:
-          name: grokkit-linux-amd64
-          path: build/grokkit
+      - name: Verify binary
+        run: |
+          ./build/grokkit --help
+          ls -lh build/grokkit