feat: added duration to transaction callback

[chittolinag]

Added transaction duration to allow us to measure the performance of SuperDoc interactions.

[Copilot]

Pull Request Overview

This PR adds transaction duration tracking to the SuperDoc editor to enable performance monitoring of editor interactions. The changes introduce a duration measurement system that captures the time taken for each transaction to complete.

• Added onTransaction callback configuration to SuperDoc
• Implemented transaction duration measurement in the Editor class
• Connected the transaction callback through the SuperDoc Vue component

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
packages/superdoc/src/core/SuperDoc.js	Added onTransaction callback configuration option
packages/superdoc/src/SuperDoc.vue	Implemented transaction callback handler to pass through duration data
packages/super-editor/src/core/Editor.js	Added duration measurement using Date.now() around transaction processing

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[harbournick]

One tiny change!

[harbournick]

LGTM