- Add background thread mechanism (prefetch_update_check/get_update_result)
so git fetch runs in parallel with skill sync and agent init
- Fix repo path fallback in check_for_updates() for dev installs
- Remove duplicate build_welcome_banner (~180 lines) and
_format_context_length from cli.py — the banner.py version is
now the single source of truth
- Port skin banner_hero/banner_logo support and terminal width check
from cli.py's version into banner.py
- Add update status output to hermes version command
- Add unit tests for update check, prefetch, and version string