feat(compact): refresh token usage after summarizing context

[0xdeafbeef]

I have read the CLA Document and I hereby sign the CLA.

This fixes that we still see prev n% context left after running compaction and it's unclear, if compaction really worked.

[github-actions]

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[0xdeafbeef]

I have read the CLA Document and I hereby sign the CLA

[0xdeafbeef]

@pakrym-oai hi, can you please take a look?

[0xdeafbeef]

Hi, any feedback?

[0xdeafbeef]

Now i can use tiktoken for more precise calc. Waiting for comments.
#5508

[etraut-openai]

Thanks for the contribution, and apologies for the slow response. We've received many PRs, and we don't have the bandwidth on the codex team to review all of them.

We've updated our contribution guidelines to clarify that we're currently accepting contributions for bugs and security fixes, but we're not generally accepting new features at this time. We need to make sure that all new features compose well with both existing and upcoming features and fit into our roadmap. If you would like to propose a new feature, please file or upvote an enhancement request in the issue tracker. We will generally prioritize new features based on community feedback.