A logo drawn from the radio's screen, to app icon guidelines (#55)

The 2004 icon is a whole radio on a transparent background and not
square, so the tab icon was padded and iOS painted the home-screen icon
on white. web/logo.svg is the radio's screen alone, its tuning scale and
orange needle, laid out as Apple's app icon guidelines ask: opaque and
full-bleed (the system cuts its own corners), a gradient background and
flat foreground layers with hard edges, no highlights or shadows of its
own, nothing thin enough to vanish at 32px. Each layer is a <g>, ready to
split out for Icon Composer. web/logo-dark.svg is the same layers
recoloured.

favicon.png (128) and apple-touch-icon.png (180) are renders of it. The
pages show it from /logo.svg, served outside the auth layer for the
sign-in page, with an app icon's rounded corners. The 2004 icon stays at
/icon.png for anything outside that links to it.

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

web/logo-dark.svg

@@ -0,0 +1,19 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1024 1024">
+  <!-- logo.svg's dark appearance: the same layers in the same places, only recoloured, as the
+       guidelines ask, so the icon reads as itself in either. -->
+  <defs>
+    <linearGradient id="bg" x1="0" y1="0" x2="0" y2="1">
+      <stop offset="0" stop-color="#1d4468"/>
+      <stop offset="1" stop-color="#0c2238"/>
+    </linearGradient>
+  </defs>
+  <g id="background"><rect width="1024" height="1024" fill="url(#bg)"/></g>
+  <g id="scale" fill="#8fc2ea">
+    <rect x="120" y="520" width="112" height="304" rx="56" opacity=".45"/>
+    <rect x="288" y="360" width="112" height="464" rx="56" opacity=".7"/>
+    <rect x="456" y="440" width="112" height="384" rx="56" opacity=".55"/>
+    <rect x="624" y="280" width="112" height="544" rx="56" opacity=".85"/>
+    <rect x="792" y="600" width="112" height="224" rx="56" opacity=".5"/>
+  </g>
+  <g id="needle"><rect x="728" y="160" width="72" height="704" rx="36" fill="#ff9f2e"/></g>
+</svg>