Install-as-app guide and iPhone safe-area support

- Install banner (phones), Settings guide and dialog with iPhone/iPad and Android steps,
  native Install button where supported; steps also on the dashboard Account page
- apple-touch-icon now a PNG (iOS ignores SVG icons)
- Shared pwa-safe.css: dark cap behind the status bar/Dynamic Island in the installed app,
  inset-aware offline banner, pull-to-refresh, bottom bars, full-screen map, dialogs
- Landscape-aware content gutters; measured top-bar height; viewport-fit=cover on every page

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

app/public/dashboard-setup.html

@@ -2,7 +2,10 @@
 <html lang="en">
 <head>
 <meta charset="UTF-8">
-<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover">
+<meta name="apple-mobile-web-app-capable" content="yes">
+<meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
+<link rel="stylesheet" href="/pwa-safe.css">
 <title>Station Dashboard — Create Account</title>
 <style>
 *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
@@ -24,6 +27,7 @@ button { width: 100%; padding: 0.7rem; background: var(--accent); color: #fff; b
 button:hover { opacity: 0.88; }
 .error { background: rgba(194,90,42,0.15); border: 1px solid var(--accent); border-radius: 8px; padding: 0.6rem 0.8rem; margin-bottom: 1rem; font-size: 0.9rem; color: var(--accent); }
 .note { margin-top: 1rem; font-size: 0.8rem; opacity: 0.55; text-align: center; }
+html, body { padding: env(safe-area-inset-top, 0px) env(safe-area-inset-right, 0px) env(safe-area-inset-bottom, 0px) env(safe-area-inset-left, 0px); }
 </style>
 </head>
 <body>