Restyle UI with a channel-strip console look and brand icon

Adds a pink/purple/blue SVG brand mark (favicon + header) and reworks
the visual language around the app's actual interaction - fader-driven
device control - via LED-style indicators, mono instrument readouts,
hairline-framed cards, console-tab nav, and an oscilloscope-style
session timeline. Leaves components/ui/* untouched, restyling only via
design tokens and the app's own composed components. Also fixes a
proxy.ts matcher gap that was gating /icon.svg behind auth.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01W8WkFF5ppURBAB918593Eb

app/(app)/control/page.tsx

@@ -4,7 +4,7 @@ export default function ControlPage() {
   return (
     <div className="flex flex-col gap-6">
       <div>
-        <h1 className="font-display text-2xl font-semibold">Control</h1>
+        <h1 className="font-heading text-2xl font-semibold">Control</h1>
         <p className="text-sm text-muted-foreground">
           Scan for devices, connect, and control them live. Every command runs directly from your browser
           to the device over Web Bluetooth - the server never sees it in real time.