feat: add Telegram release notifications

[ineedjet]

🤖 [rubykatzen/baseline]:

Summary

• add a reusable workflow for Telegram notifications on published releases
• add a release message formatter and reuse the existing Telegram sender
• make Baseline consume its own shared workflow
• document the consumer workflow and cover formatting, events, permissions, and secrets

Published prereleases are included through the release.published event. Distinct release names are shown without duplicating the common case where the name equals the tag.

Closes #169.

Verification

• python3 -m unittest discover -s test -v
• pre-commit run --all-files

📦 🔔 ✅