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>

CHANGELOG.md

@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- A new logo, on every page, in the browser tab and on the home screen: the old radio's screen,
+  its tuning scale and orange needle, drawn flat to Apple's app icon guidelines, with a dark
+  version. The 2004 icon is still at /icon.png.
 - Words that hide items. Settings has a list for every feed you read, and each feed's settings a
   list of its own; an item with one of those words or phrases in its title or text is hidden
   from you and is not downloaded on your account. Other people's lists never hide anything from