fix: symlink-safe CLI entrypoint and npm publish verification backoff

[bearmug]

Summary

This PR fixes two concrete issues in the current branch:

• repo-arch now runs correctly through the Homebrew symlinked shim
• npm publish verification now retries with backoff to handle registry propagation delay

What changed

• src/cli.ts now resolves the entrypoint by realpath, so repo-arch --help and subcommands work when invoked through /opt/homebrew/bin/repo-arch
• .github/workflows/publish.yml now verifies the published name@version with bounded exponential backoff instead of a single sleep 10

Validation

• npm run typecheck
• npm test
• npm run build
• workflow YAML parses successfully

Notes

This PR is intentionally narrow and matches the current diff against main.