Generalize dashboard panel expansion: Stream / On Watch / Pulse / Wires
each get a chevron toggle persisted in localStorage under
dashboard_section_state (migrates legacy dashboard_chart_visible). Drop
the redundant inner border on EventChart so it doesn't double-frame the
panel. Mobile "more" sheet becomes full-height with translucent glass
(rgba(...,0.72) + 28px blur) instead of nearly-solid.
alexei.dolgolyov
9eb76c1407