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/LoginPage.tsx

@@ -44,32 +44,6 @@ export function LoginPage() {
     <>
     <PageMeta title="Sign In" description="Sign in to your ResolutionFlow account" />
     <div className="flex min-h-screen items-center justify-center bg-background px-4">
-      {/* Atmosphere orbs */}
-      <div
-        className="pointer-events-none fixed z-0"
-        style={{
-          top: '-120px',
-          right: '-80px',
-          width: '600px',
-          height: '600px',
-          borderRadius: '50%',
-          background: 'radial-gradient(circle, rgba(6, 182, 212, 0.15) 0%, rgba(6, 182, 212, 0.04) 40%, transparent 70%)',
-          filter: 'blur(60px)',
-        }}
-      />
-      <div
-        className="pointer-events-none fixed z-0"
-        style={{
-          bottom: '-100px',
-          left: '-60px',
-          width: '500px',
-          height: '500px',
-          borderRadius: '50%',
-          background: 'radial-gradient(circle, rgba(139, 92, 246, 0.08) 0%, rgba(139, 92, 246, 0.02) 40%, transparent 70%)',
-          filter: 'blur(60px)',
-        }}
-      />
-
       <div className="relative z-10 w-full max-w-md space-y-8">
         <div className="text-center">
           <div className="mb-4 flex justify-center sm:mb-6">