Harden dashboard state transitions and standardize to a professional monochrome UI

[Copilot]

This change addresses UI inconsistency and runtime friction in the dashboard by tightening control-state logic and applying a consistent black/white visual system. It focuses on removing interaction ambiguity while keeping behavior predictable during live updates.

• State logic fixes

  • Synced PHANTOM toggle behavior with A/B mode transitions so the controls no longer drift into conflicting states.
  • Updated mode/toggle handlers to derive next state atomically from prior state.

• Runtime UX correction

  • Initialized the clock state on first render to avoid an empty timestamp in the top bar before the first interval tick.

• Professional black/white redesign

  • Replaced accent-heavy palette usage with grayscale tokens across panels, badges, graphs, alerts, and bars.
  • Kept visual hierarchy via contrast and weight rather than color saturation.

<button onClick={() => {
  setPhantom(p => {
    const next = !p;
    setMode(next ? "PHANTOM" : "HPA");
    return next;
  });
}}>
  {phantom ? "◉ PHANTOM ON" : "○ PHANTOM OFF"}
</button>