fix(tracking): update tiktok event mapping

Summary by CodeRabbit

• Bug Fixes

  • Corrected TikTok event mapping so first-vote events are now tracked as "Subscribe" for improved attribution.

• Refactor

  • Tracking now only fires for recognized actions, reducing noise and improving data quality.
  • Event resolution and logging streamlined for clearer developer insights and consistent production behavior.

• Documentation

  • Added clarification on TikTok event mapping for easier maintenance.