style: light theme and hand-inked logo matching acampada26s.net

The previous pass kept the dark base and the red icons, which did not
read as the acampada. Now:

- Light theme: white page, black ink and borders, black buttons with a
  hard neon offset shadow, neon for focus and the active nav item;
  h1/h2 in Anton with the stepped neon shadow of the site headings.
- Nav, empty-state, spinner and pattern assets in black; platform icons
  keep their dark disc with a neon stroke.
- New mark: three dome tents wired from their doors into a switch with
  an antenna, drawn in the inked style of the acampada logo (curved
  poles, ball ends, hatching) over a neon offset copy. LogoMark renders
  it inline; visible product name is T-HUB.
- docs/brand: t-hub.svg and a lockup with the Anton wordmark converted
  to outlines so it renders without the font.
- Public submission page moved to the light palette.

Checked with headless Chromium screenshots (offline sample data) on
desktop and mobile.

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

apps/web/public/brand/icon-mastodon.svg

@@ -1,6 +1,6 @@
 <svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 1700 1700">
   <title>Mastodon</title>
-  <circle cx="850" cy="850" r="560" fill="#0a0a0b" stroke="#FF1610" stroke-width="38"
+  <circle cx="850" cy="850" r="560" fill="#0a0a0b" stroke="#00E5FF" stroke-width="38"
           transform="rotate(-17.5 850 850)"/>
-  <path d="M 400 500 L 400 700 Q 400 780 480 780 L 520 780 Q 560 780 560 740 L 560 560 Q 560 540 580 540 Q 600 540 600 560 L 600 740 Q 600 780 640 780 L 680 780 Q 760 780 760 700 L 760 500 Q 760 420 680 420 L 520 420 Q 440 420 400 500 Z M 400 500 L 360 460 Q 320 420 320 500 L 320 660 Q 320 740 380 760" fill="none" stroke="#FF1610" stroke-width="35" stroke-linecap="round" stroke-linejoin="round"/>
+  <path d="M 400 500 L 400 700 Q 400 780 480 780 L 520 780 Q 560 780 560 740 L 560 560 Q 560 540 580 540 Q 600 540 600 560 L 600 740 Q 600 780 640 780 L 680 780 Q 760 780 760 700 L 760 500 Q 760 420 680 420 L 520 420 Q 440 420 400 500 Z M 400 500 L 360 460 Q 320 420 320 500 L 320 660 Q 320 740 380 760" fill="none" stroke="#00E5FF" stroke-width="35" stroke-linecap="round" stroke-linejoin="round"/>
 </svg>