Tracks 9 key events: account_created, login_success, flow_viewed,
session_started, session_completed, export_generated, ai_feature_used,
psa_connected, session_shared. Identifies users on login, resets on
logout. Autocapture disabled — only explicit discrete events.
Set VITE_POSTHOG_KEY in environment to enable.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
