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-5-agentic-development/data/guides/SESSION-PROTOCOL.md

@@ -0,0 +1,46 @@
+# Session Start Protocol
+
+When starting or resuming a session, **always follow this sequence before implementing anything:**
+
+## 1. Read the Dialog Document
+
+Read the dialog file completely to understand:
+- What steps are done
+- What steps remain
+- Any blockers or change requests
+- Current context and decisions
+
+## 2. Verify Plan Against Reality
+
+**The plan may be outdated.** Check if:
+- Steps marked "To Do" have actually been implemented
+- Steps marked "Done" are truly complete
+- Numbering is sequential and accurate
+
+If the plan is outdated → Update it before proceeding.
+
+## 3. Present Current Status
+
+Summarize for the designer:
+- What's done (with step numbers)
+- What's remaining (with step numbers)
+- Any change requests pending
+
+## 4. Before Implementing a Step
+
+**Always check the specification/sketches first:**
+
+```
+Agent: "Before implementing step 20, let me check the sketches..."
+Agent: "I see this requires a nested drawer pattern, not inline buttons.
+        Should I break this into sub-steps?"
+```
+
+This prevents building the wrong thing and wasting effort.
+
+## Why This Matters
+
+Sessions can be interrupted. Context can be lost. The dialog document survives — but only if it's kept accurate. This protocol ensures:
+- No duplicate work (re-implementing what exists)
+- No missed work (skipping what's actually needed)
+- Correct understanding of requirements before implementation