feat: add Discord verification bot

[jamilahmadzai]

Closes #29

Summary

• Adds a Discord bot example for team workflow verification.
• Provides /aport-verify and /aport-help slash commands.
• Sends selected action, Discord metadata, and optional JSON context to APort.
• Returns private approval/denial embeds with policy and reason details.
• Includes command registration, environment sample, setup docs, and tests.
• Adds the Discord bot to the root developer tools table.

Testing

cd examples/developer-tools/discord-bot
npm install --no-audit
npm test
npm run check
npm pack --dry-run
git diff --check

Payout

Payment method: PayPal jamilurrehman722@gmail.com.