Shorten over-long godoc/inline comments across the client/ui tray and
services code: drop narrative restatement, legacy-Fyne tangents, and text
already evident from signatures and names. Keep only the non-obvious why
(concurrency/lock ordering, platform quirks, ordering constraints, the
profile-switch state table). No code changes.
Adds an end-to-end SSO session-extension feature: the management server
publishes per-peer session deadlines on every Login/Sync, a new
ExtendAuthSession RPC refreshes the deadline using a fresh JWT without
tearing down the tunnel, and the daemon tracks the deadline locally so
the UI can fire a T-10min warning toast with an interactive "Extend now"
action.
Zoltan Papp