- Always light (Atlassian-style), no more automatic dark mode
- Each calendar tooltip entry and each recent commit links directly to
the forge issue/PR/commit or the Radicle explorer page it produced
- Fixed the tooltip being clipped by the calendar's horizontal scroll
container (overflow-y: visible instead of the inherited overflow: auto)
- Footer with the source repository link and license
- activity_log now stores a URL per entry; new optional config fields
source_url (footer link) and radicle.explorer_url (Radicle links)

rad issue open --quiet never prints the created issue's id (only a sync
summary), which silently corrupted the stored radicle_id and caused every
issue to be re-mirrored on each pass. Fixed by dropping --quiet and parsing
the id out of the normal output box instead.

Also adds an append-only activity_log table and a small HTTP dashboard
(GitHub-style activity calendar + recent commits list) served alongside
the existing /healthz and /api/status endpoints.

Reworded sentences for clarity and conciseness in the README.