Wrap the existing version label in the welcome-banner panel title
('Hermes Agent v… · upstream … · local …') with an OSC-8 terminal
hyperlink pointing at the latest git tag's GitHub release page
(https://github.com/NousResearch/hermes-agent/releases/tag/<tag>).
Clickable in modern terminals (iTerm2, WezTerm, Windows Terminal,
GNOME Terminal, Kitty, etc.); degrades to plain text on terminals
without OSC-8 support. No new line added to the banner.
New get_latest_release_tag() helper runs 'git describe --tags
--abbrev=0' in the Hermes checkout (3s timeout, per-process cache,
silent fallback for non-git/pip installs and forks without tags).