fix: eliminate deprecated cyan, glass-border, and off-palette colors site-wide

- Replace all rgba(6,182,212,...) cyan focus borders and accents with
  rgba(249,115,22,...) ember orange across 21+ component files
- Remove all var(--glass-border) references (undefined variable) with
  var(--color-border-default) across 24 files
- Remove deprecated blur orbs and glass-morphism effects from
  SurveyPage, SurveyThankYouPage, and LoginPage
- Migrate landing.css from hardcoded hex to CSS custom properties
  (~97 replacements for single-source theming)
- Fix off-palette grays in FlowPilotAnalyticsPage chart styling
  (#8891a0 → #848b9b, #18191f → var(--color-bg-card))
- Update stale comments: "cyan brand" → "accent brand" in GlowEdge,
  "gradient cyan square" → "gradient orange square" in BrandLogo
- Rename glow-cyan SVG filter ID to glow-accent
- Fix category color comment: "cyan" → "deep orange"

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/ReviewQueuePage.tsx

@@ -87,7 +87,7 @@ export default function ReviewQueuePage() {
   return (
     <div className="flex h-full flex-col lg:flex-row overflow-hidden">
       {/* Left panel — Proposal list */}
-      <div className="w-full shrink-0 border-b lg:border-b-0 lg:border-r lg:w-[380px] overflow-y-auto" style={{ borderColor: 'var(--glass-border)' }}>
+      <div className="w-full shrink-0 border-b lg:border-b-0 lg:border-r lg:w-[380px] overflow-y-auto" style={{ borderColor: 'var(--color-border-default)' }}>
         {/* Header */}
         <div className="sticky top-0 z-10 p-3 sm:p-4 space-y-3" style={{ background: 'rgba(16, 17, 20, 0.95)', }}>
           <div className="flex items-center justify-between">