Add browser-plugin-bot-detection wrapping FingerprintJS BotD (#1460)

* Add browser-plugin-bot-detection wrapping FingerprintJS BotD

Introduces a new browser tracker plugin that detects bots client-side
using @fingerprintjs/botd and attaches the result as a
client_side_bot_detection context entity to all tracked events.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>