feat: design system overhaul — sidebar, AI chats, settings, brainstorm, color cleanup

- Sidebar: dynamic brand-accent colors, brainstorm section restyled
- AI chat general: popup panel with expand/collapse, hides when contextual AI open
- AI chat contextual: tabs reordered (Actions first), X close button, height fix
- Settings: all tabs restyled, 6 new color presets (sage, terracotta, iron, etc.)
- Global color cleanup: emerald/orange hardcoded → brand-accent dynamic
- Brainstorm page: orange → brand-accent throughout
- PageEntry animation component added to key pages
- Floating AI button: bg-brand-accent instead of hardcoded black
- i18n: all 15 locales updated with new AI/billing keys
- Billing: freemium quota tracking, BYOK, stripe subscription scaffolding
- Admin: integrated into new design
- AGENTS.md + CLAUDE.md project rules added

.agent/skills/wds-4-ux-design/data/page-creation-flows/flow-a-sketch.md

@@ -0,0 +1,28 @@
+# Flow A: Sketch Path
+
+**Activates when:** User chooses to draw a sketch (physical/digital)
+
+---
+
+## Process
+
+<output>**Perfect! Let's set up for your sketch.**
+
+I'll create:
+1. Page placeholder with navigation
+2. Sketches folder ready for upload
+3. Basic page structure
+
+When you're ready, upload your sketch and we'll analyze it together using the Page Process Workshop.</output>
+
+---
+
+## Actions
+
+1. Run `page-init-lightweight.md` to create structure
+2. User uploads sketch when ready
+3. Return to `workshop-page-process.md` for analysis
+
+---
+
+**This is the preferred path - sketches capture design intent best.**