chore: archival announcement

[theochap]

Description

Last commit before archiving op-rs/kona

[Copilot]

Pull request overview

This PR updates the README to announce that the op-rs/kona repository has been archived after transferring to the Optimism monorepo. The previous forward-looking announcement about the planned archival in mid-January 2026 is replaced with a current statement confirming the archival has occurred as of January 15th, 2026.

Changes:

• Replaced future-tense archival notice with present-tense confirmation that the repository has been archived
• Simplified the message from multiple paragraphs to two concise sentences
• Updated references to use HTML anchor tags for consistency

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[Copilot]

Extra period at the end. There's a period inside the anchor tag followed by another period, resulting in '!.'

Suggested change

	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in <a href="https://github.com/ethereum-optimism/optimism">https://github.com/ethereum-optimism/optimism</a>!.
	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in <a href="https://github.com/ethereum-optimism/optimism">https://github.com/ethereum-optimism/optimism</a>!

[sebastianst]

yep, should be removed

[sebastianst]

and why not a markdown link?

Suggested change

	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in <a href="https://github.com/ethereum-optimism/optimism">https://github.com/ethereum-optimism/optimism</a>!.
	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in [ethereum-optimism/optimism](https://github.com/ethereum-optimism/optimism)!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.7%. Comparing base (3c02e71) to head (4d2f6b1).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

❗ There is a different number of reports uploaded between BASE (3c02e71) and HEAD (4d2f6b1). Click for more details.

HEAD has 18 uploads less than BASE

Flag	BASE (3c02e71)	HEAD (4d2f6b1)
proof	7	0
e2e	10	0
unit	2	1

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[sebastianst]

yep, should be removed

[sebastianst]

and why not a markdown link?

Suggested change

	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in <a href="https://github.com/ethereum-optimism/optimism">https://github.com/ethereum-optimism/optimism</a>!.
	The commit history was conserved. Thank you very much for contributing to `op-rs/kona` and see you in [ethereum-optimism/optimism](https://github.com/ethereum-optimism/optimism)!