fix(webview): update native callback lifetime and test coverage instrumentation

.github/workflows/test.yml

@@ -96,16 +96,14 @@ jobs:
         run: |
           sudo apt-get update -y
           sudo apt-get install -y libgtk-3-dev libwebkit2gtk-4.1-dev xvfb
-      - name: Resolve native crash address
+      - name: Test webview
         if: runner.os == 'Linux'
+        # Match the full suite's coverage instrumentation and repeat on the same
+        # GTK event loop to catch queued callbacks after engine destruction.
         run: |
           PACKAGES=$(go list ./... | awk '!/\/bind\// && (!/\/cmd\// || /\/cmd\/web$/)')
           go test -c -tags webview -coverpkg=$(echo "$PACKAGES" | paste -sd "," -) -covermode=count -o "$RUNNER_TEMP/goprovider.test" ./internal/webview/goprovider
-          addr2line -a -f -C -e "$RUNNER_TEMP/goprovider.test" 0xaaddaf
-      - name: Test webview
-        if: runner.os == 'Linux'
-        # Repeat on the same GTK event loop to catch callbacks after destruction.
-        run: xvfb-run -a go test -tags webview -v -count=5 -timeout 300s ./internal/webview/goprovider/
+          xvfb-run -a "$RUNNER_TEMP/goprovider.test" -test.v -test.count=5 -test.timeout=300s -test.coverprofile="$RUNNER_TEMP/webview-coverage.out"
         env:
           CGO_ENABLED: 1
       - name: Test webview