Add Pro Feature

Add a new feature gated behind Pro Mode (dump-pro-mode localStorage preference).

Steps

1. Implement the feature — gate it behind the proMode boolean:

   • In Canvas.tsx: const [proMode] = useLocalStorage(PRO_MODE_STORAGE_KEY, false); (already exists)
   • In other components: const [proMode] = useLocalStorage(PRO_MODE_STORAGE_KEY, false); with import import { PRO_MODE_STORAGE_KEY } from "@/lib/chat-providers"; and import { useLocalStorage } from "@/hooks/useLocalStorage";
   • Wrap the feature's UI with {proMode && ( ... )}

2. Add to the welcome dialog in src/components/canvas/Canvas.tsx:

   • Find the Pro Mode Enabled dialog (search for proWelcomeOpen)
   • Add a new entry to the features array with { icon: IconName, label: "Short name", desc: "One-line description" }
   • Import the lucide icon if not already imported

3. Document on the help page at src/app/help/pro-mode/page.tsx:

   • Add a new entry to the PRO_FEATURES array with:
     • icon: lucide-react icon component
     • title: feature name (2-4 words)
     • description: 1-2 sentences explaining the feature
     • color: one of blue, violet, green, orange, indigo, amber — pick one not already heavily used, or add a new color to COLOR_MAP
   • Import the icon from lucide-react if not already imported

Key files

• src/lib/chat-providers.ts — PRO_MODE_STORAGE_KEY constant
• src/components/canvas/Canvas.tsx — pro mode toggle, welcome dialog, canvas features
• src/components/board/BoardSettings.tsx — board settings (context type, system prompt, RSS)
• src/components/board/ChatButton.tsx — AI chat prompt dialog
• src/app/b/[boardId]/page.tsx — board page (view switcher)
• src/app/help/pro-mode/page.tsx — help page listing all pro features

Style guide

• Keep welcome dialog entries concise: label (2-4 words) + desc (under 60 chars)
• Help page descriptions: 1-2 full sentences explaining what the feature does
• Always gate behind proMode — never show pro features by default
• Use existing patterns: useLocalStorage for reading the preference, lucide icons for UI