feat(discord-bot): add SolFoundry Discord Bot with bounty notifications

[zengbinli]

Bounty: Discord Bot for Bounty Notifications

Bounty: #853 | Reward: 500K $FNDRY | Tier: T2 | Domain: Integration

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What This PR Delivers

A fully functional Discord bot that posts new bounties, displays leaderboards, and allows users to filter notifications by bounty type and reward level.

Architecture

automaton/discord-bot/
├── index.ts                    # Bot entry point, rich embed builder
├── package.json                # Dependencies (discord.js v14)
├── tsconfig.json               # TypeScript config
├── README.md                   # Setup & usage guide
├── services/
│   └── bounty-poller.ts        # Periodic API polling with EventEmitter
├── commands/
│   └── index.ts                # Slash command handlers
├── utils/
│   └── format.ts               # Tier colors, reward formatting
└── __tests__/
    └── bot.test.ts             # Vitest unit tests

Features

Feature	Implementation
New bounty notifications	Rich embeds with tier color, reward, domain
Polling	Every 5 minutes (configurable), event-driven
/bounties	List bounties with tier/domain filters
/leaderboard	Top contributors with medals
/subscribe	Per-user notification filters (tier, reward, domain)
/unsubscribe	Remove preferences
/status	Bot uptime, tracked bounties, subscriptions

Acceptance Criteria Met

• New bounty postings with rich embeds
• Leaderboard command with top contributors
• Customizable notification filters per user

Setup

# Environment
DISCORD_BOT_TOKEN=your-token
DISCORD_CHANNEL_ID=your-channel
DISCORD_GUILD_ID=your-guild
DISCORD_CLIENT_ID=your-app-id
SOLFOUNDRY_API_URL=https://api.solfoundry.io

# Run
npm install && npm start

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Wallet: 3D2uVzAsGhrWfUprHLwezCNkE1u9eK7SH2MAhbC3gFVN