fix(release): replace @semantic-release/git with PR-based release asset workflow

[akadenia-leaf]

Problem

@semantic-release/git tries to push package.json/CHANGELOG.md directly to main, which is blocked by the branch protection ruleset (requires PRs + status checks).

Solution

• Remove @semantic-release/git
• Add scripts/commit-release-assets.sh — on successful release, creates a chore/release-X.Y.Z branch with the updated assets and opens a PR automatically
• npm publish + GitHub release still happen as before
• main stays fully protected 🔒

🤖 Generated with Claude Code

Summary by CodeRabbit

• Chores
  • Enhanced release process with additional verification checks to ensure deployment prerequisites are met before version releases.