Redesign: phosphor-terminal identity and simplified 4-page structure

Information architecture (6 nav destinations -> 4):
- New Overview home: metric strip (live setups, high confidence,
  hit rate, expectancy), top-5 setups, watchlist pulse
- Market = Watchlist + Rankings merged as tabs; scoring weights
  moved into a collapsible disclosure
- Signals = Scanner + Performance merged as tabs (Setups | Track
  Record) with actions inside the panels
- Legacy routes redirect (/watchlist, /rankings, /scanner,
  /performance)

Visual identity:
- Warm ash-green dark palette replaces cold navy; citron lime
  accent replaces blue (Tailwind gray/blue remapped at config
  level so all components reskin)
- Primary buttons: lime with ink text; long/short stays
  emerald/red
- Typography: Bricolage Grotesque display, Instrument Sans body,
  IBM Plex Mono for all numerals incl. chart canvas labels
- Atmosphere: graph-paper grid + citron glow + film grain;
  pulsing brand dot; mono-numbered nav

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/components/layout/MobileNav.tsx

@@ -3,10 +3,9 @@ import { NavLink } from 'react-router-dom';
 import { useAuthStore } from '../../stores/authStore';
 
 const navItems = [
-  { to: '/watchlist', label: 'Watchlist' },
-  { to: '/scanner', label: 'Scanner' },
-  { to: '/rankings', label: 'Rankings' },
-  { to: '/performance', label: 'Performance' },
+  { to: '/', label: 'Overview', end: true },
+  { to: '/market', label: 'Market', end: false },
+  { to: '/signals', label: 'Signals', end: false },
 ];
 
 export default function MobileNav() {
@@ -16,7 +15,13 @@ export default function MobileNav() {
   return (
     <div className="lg:hidden">
       <div className="flex items-center justify-between px-4 py-3 glass rounded-none border-x-0 border-t-0">
-        <h1 className="text-lg font-semibold text-gradient">Signal Dashboard</h1>
+        <div className="flex items-center gap-2">
+          <span className="relative flex h-2 w-2">
+            <span className="absolute inline-flex h-full w-full rounded-full bg-blue-400 animate-signal-pulse" />
+            <span className="relative inline-flex h-2 w-2 rounded-full bg-blue-400/60" />
+          </span>
+          <h1 className="font-display text-lg font-bold tracking-tight text-gradient">Signal</h1>
+        </div>
         <button
           onClick={() => setOpen((v) => !v)}
           className="p-2 text-gray-400 hover:text-gray-200 transition-colors duration-200"
@@ -40,15 +45,16 @@ export default function MobileNav() {
         }`}
       >
         <nav className="px-3 py-2 space-y-1">
-          {navItems.map(({ to, label }) => (
+          {navItems.map(({ to, label, end }) => (
             <NavLink
               key={to}
               to={to}
+              end={end}
               onClick={() => setOpen(false)}
               className={({ isActive }) =>
                 `block px-3 py-2.5 rounded-lg text-sm font-medium transition-all duration-200 ${
                   isActive
-                    ? 'bg-white/[0.08] text-white'
+                    ? 'bg-blue-400/[0.08] text-blue-300'
                     : 'text-gray-400 hover:bg-white/[0.04] hover:text-gray-200'
                 }`
               }
@@ -63,7 +69,7 @@ export default function MobileNav() {
               className={({ isActive }) =>
                 `block px-3 py-2.5 rounded-lg text-sm font-medium transition-all duration-200 ${
                   isActive
-                    ? 'bg-white/[0.08] text-white'
+                    ? 'bg-blue-400/[0.08] text-blue-300'
                     : 'text-gray-400 hover:bg-white/[0.04] hover:text-gray-200'
                 }`
               }