v0.18.5

Fixed

• Long-run freeze / memory bloat in the live viewer. Leaving the TUI
  open for hours with a busy session selected grew it to hundreds of MB
  of RSS and eventually froze it — unresponsive to Ctrl+C / q. The
  per-session history cache was unbounded (it kept the full parsed
  activity array of every session ever selected) and returned a fresh
  array on every cache hit, so the viewer re-rendered on every 2s
  refresh even when nothing changed. The cache is now LRU-bounded and
  returns a stable reference on a hit, so memory stays flat and an
  unchanged refresh does no work.