✨ Add Multi-Outcome Market Support

[Mosas2000]

Description

Currently the platform only supports binary (Yes/No) markets. The market-multi.clar contract exists but is not integrated with the frontend.

Current State

• contracts/market-multi.clar exists for multi-outcome markets
• tests/market-multi.test.ts exists
• scripts/multi-outcome-trading.ts exists
• Frontend only supports binary markets

Proposed Features

1. Multi-Outcome Market Display

Instead of just Yes/No, show multiple outcomes:

Who will win the 2026 World Cup?
├── 🇧🇷 Brazil - 35%
├── 🇫🇷 France - 28%
├── 🇦🇷 Argentina - 22%
├── 🇩🇪 Germany - 10%
└── 📦 Other - 5%

2. Multi-Outcome Trading

• Select from multiple options
• Dynamic odds calculation
• Same stake/claim mechanics

3. Market Type Indicator

• Binary markets: Standard Yes/No UI
• Multi-outcome: Expandable options list

4. Create Multi-Outcome Markets

• Add outcomes (min 3, max 10)
• Set initial odds (optional)
• Set resolution criteria

UI Mockup

┌─ Multi-Outcome Market ───────────────────┐
│ Who will win the 2026 World Cup?         │
│                                          │
│ ○ 🇧🇷 Brazil          35.2%    [Stake]   │
│   ████████████████░░░░░░░░░░░░           │
│                                          │
│ ○ 🇫🇷 France          28.1%    [Stake]   │
│   █████████████░░░░░░░░░░░░░░            │
│                                          │
│ ○ 🇦🇷 Argentina        22.0%   [Stake]   │
│   ██████████░░░░░░░░░░░░░░░░░            │
│                                          │
│ Total Pool: 1,245 STX                    │
└──────────────────────────────────────────┘

Files to Create/Modify

• frontend/src/types/market.ts - Add multi-outcome types
• frontend/src/hooks/useMultiMarket.ts (new)
• frontend/src/components/MultiOutcomeCard.tsx (new)
• frontend/src/pages/MultiTradePage.tsx (new)
• Connect to contracts/market-multi.clar

Priority

🟢 Low - Advanced feature for future