v0.22.0 — Solar switch + resume-mode

Added: a Solar-charging on/off switch (mirrors the app's Solar Charging toggle — on restores your last solar Eco-Smart mode, off disables it), and a "return the charger to …" preference (Leave as set / Full Green / Eco Smart / Disabled) so after a managed charge the assistant hands back to your chosen native mode. 185-case test suite.