Draft changelog: Sep 26, 2026 X API updates

[mintlify]

Summary

Adds a weekly changelog entry covering product changes shipped since the Sep 21 entry.

Changes

• New features: X Activity API subscription expires_at, OAuth 2.0 webhook signature header, is_moderator in broadcast.chat
• Updates: broadcast scopes in token exchange, Chat join-request approval, Livestream API access form, 128 MB batch compliance limit, source removed from tweet.fields

Context

Sourced from PRs #438–#459 and OpenAPI spec updates merged Sep 21–26.

[mintlify]

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Project	Status	Preview	Updated
x-corp	🟢 Ready	View Preview	Sep 26, 2026, 2:12 AM

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