[mackysoft]

Summary

• Use <package-id>-<version> for both .unitypackage and signed UPM release assets.

Scope

• Read the asset basename from the prepared package manifest and reuse it for the Unity package export, artifact transfer, and Release attachment.
• Record the naming rule in the maintainer release instructions.

Verification

• Stable and prerelease metadata checks passed using temporary local Git repositories.
• Bash syntax, ShellCheck, and workflow expression checks passed. Actionlint's existing create-github-app-token@v3 input metadata false positives were excluded.
• No Unity source, asset, or test setup changes; no additional Editor test run is required for this change.