Draft changelog: block endpoints, subscription events, broadcast scopes

[mintlify]

Summary

Adds a Sep 9, 2026 changelog entry covering product changes shipped since the Sep 1 entry.

Changes

• Enterprise-only block (POST /2/users/{id}/blocking) and unblock (DELETE /2/users/{source_user_id}/blocking/{target_user_id}) endpoints (Add Enterprise-only block and unblock user endpoints #404)
• subscriptions.subscribe / subscriptions.unsubscribe events for the X Activity API, with direction filter support (Add subscription event types to X Activity API docs #402)
• New broadcast.read and broadcast.write OAuth 2.0 scopes (Add broadcast scopes to OAuth 2.0 scopes table #350)

Context

Based on the three PRs merged to main since the last changelog entry (Sep 1, 2026).

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Project	Status	Preview	Updated
x-corp	🟢 Ready	View Preview	Sep 10, 2026, 2:14 AM

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