chore(deps): update github artifact actions to v4

.gitea/workflows/ci.yaml

@@ -25,7 +25,7 @@ jobs:
       # Download baseline coverage from main branch (for PRs)
       - name: Download baseline coverage
         if: gitea.event_name == 'pull_request'
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: coverage-baseline
           path: ./baseline
@@ -53,7 +53,7 @@ jobs:
       # Upload coverage as baseline (only on main)
       - name: Upload coverage baseline
         if: gitea.ref == 'refs/heads/main'
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: coverage-baseline
           path: coverage.txt