feat: dashboard visual overhaul — amber/blue/danger accents, Inter + JetBrains Mono, sharp corners, tighter density

- Tailwind config: semantic color tokens (amber/blue/danger), borderRadius all zero except full, Inter + JetBrains Mono font families
- index.css: Google Fonts imports, sharp scrollbar, scanline card texture, amber-glow utility
- Dashboard.tsx: three-color accent system (amber primary, blue informational, danger alerts), Inter for labels/prose, JetBrains Mono strictly for data values, all rounded corners removed, tighter spacing (p-4 cards, gap-4 grids, space-y-2 lists), underline-style tabs with amber active indicator, band condition dot indicators, source status dots remapped to semantic colors, StatCard supports per-instance value coloring, 36px minimum touch targets on interactive elements

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dashboard-frontend/tailwind.config.ts

@@ -4,20 +4,57 @@ export default {
   content: ['./index.html', './src/**/*.{ts,tsx}'],
   darkMode: 'class',
   theme: {
+    borderRadius: {
+      none: '0',
+      DEFAULT: '0',
+      sm: '0',
+      md: '0',
+      lg: '0',
+      xl: '0',
+      '2xl': '0',
+      full: '9999px',
+    },
     extend: {
       colors: {
         bg: {
           DEFAULT: '#0a0e17',
-          card: '#111827',
-          hover: '#1a2332',
+          card: '#0f1520',
+          hover: '#162030',
+          elevated: '#1a2535',
         },
         border: {
-          DEFAULT: '#1e2a3a',
-          light: '#2d3a4d',
+          DEFAULT: '#1c2a3a',
+          light: '#243345',
+          bright: '#2d4060',
+        },
+        amber: {
+          DEFAULT: '#f59e0b',
+          dim: '#d97706',
+          glow: '#fbbf24',
+          muted: 'rgba(245,158,11,0.15)',
+        },
+        blue: {
+          DEFAULT: '#38bdf8',
+          dim: '#0ea5e9',
+          muted: 'rgba(56,189,248,0.12)',
+        },
+        danger: {
+          DEFAULT: '#f97316',
+          dim: '#ea580c',
+          muted: 'rgba(249,115,22,0.15)',
+        },
+        slate: {
+          100: '#f1f5f9',
+          200: '#e2e8f0',
+          300: '#cbd5e1',
+          400: '#94a3b8',
+          500: '#64748b',
+          600: '#475569',
+          700: '#334155',
         },
-        accent: '#3b82f6',
       },
       fontFamily: {
+        sans: ['Inter', 'system-ui', '-apple-system', 'sans-serif'],
         mono: ['JetBrains Mono', 'monospace'],
       },
     },