fix: ensure previous transitions are properly aborted

[dummdidumm]

• nullify options when the transition is aborted. This ensures a change in options is reflected the next time, else it would stick around indefinetly
• abort previous intro (if exists) when new intro plays (same for outro)

fixes #11372

tried to come up with a test but failed

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[changeset-bot]

🦋 Changeset detected

Latest commit: dc6d9e2

The changes in this PR will be included in the next version bump.

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[trueadm]

This fixes a bunch of local issues I found!