refactor: replace cyan accent with ember orange across entire frontend

Swap accent color from cyan (#22d3ee) to ember orange (#f97316) site-wide.
Cyan caused contrast issues and felt generic — orange brings warmth and
urgency fitting for a troubleshooting tool.

Changes:
- CSS variables: accent, accent-hover, accent-dim, accent-text, primary, ring
- Warning color shifted from amber (#fbbf24) to yellow (#eab308) for
  semantic separation from orange accent
- Brand SVGs: logo gradient updated to orange
- 50+ component files: all hardcoded cyan hex values, Tailwind cyan-*
  classes, and rgba(34,211,238,...) glow values replaced
- landing.css: all 45+ cyan references + 5 old border color fixes
- DESIGN-SYSTEM.md bumped to v5 with decisions log
- CLAUDE.md: all color references synced to charcoal palette + orange accent
- PWA theme-color meta tag updated to match sidebar (#10121a)

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

frontend/src/components/flowpilot/FlowPilotActionBar.tsx

@@ -108,7 +108,7 @@ export function FlowPilotActionBar({
           <button
             onClick={() => setShowStatusUpdate(true)}
             disabled={isProcessing}
-            className="flex items-center justify-center gap-1.5 rounded-lg bg-cyan-500/10 border border-cyan-500/20 px-2.5 sm:px-4 py-2 min-h-[40px] sm:min-h-[44px] text-xs sm:text-sm font-medium text-cyan-400 hover:bg-cyan-500/20 disabled:opacity-40 disabled:pointer-events-none transition-colors"
+            className="flex items-center justify-center gap-1.5 rounded-lg bg-orange-500/10 border border-orange-500/20 px-2.5 sm:px-4 py-2 min-h-[40px] sm:min-h-[44px] text-xs sm:text-sm font-medium text-orange-400 hover:bg-orange-500/20 disabled:opacity-40 disabled:pointer-events-none transition-colors"
             title="Share Update"
           >
             <FileText size={15} />
@@ -152,7 +152,7 @@ export function FlowPilotActionBar({
               value={resolutionSummary}
               onChange={(e) => setResolutionSummary(e.target.value)}
               placeholder="What resolved the issue?"
-              className="w-full rounded-lg border border-border bg-card px-3 py-2 text-sm text-foreground placeholder:text-muted-foreground focus:border-[rgba(6,182,212,0.3)] focus:outline-none resize-none"
+              className="w-full rounded-lg border border-border bg-card px-3 py-2 text-sm text-foreground placeholder:text-muted-foreground focus:border-[rgba(249,115,22,0.3)] focus:outline-none resize-none"
               rows={4}
               autoFocus
             />