H-6080: Add changeset for @hashintel/ds-theme

[CiaranMn]

🌟 What is the purpose of this PR?

To make @hashintel/ds-theme usable outside of the repo, we need to publish it. This PR adds a changeset file to do so.

Once this PR is merged, #8255 will pick it up, and we can merge the latter to publish the latest state of the packages it lists.

[cursor]

PR Summary

Prepares @hashintel/ds-theme for publication and synchronizes versions across the workspace.

• Adds a changeset marking a patch release for @hashintel/ds-theme
• Sets @hashintel/ds-theme version to 0.0.0 and updates devDependency references in ds-components and ds-helpers
• Updates yarn.lock to reflect version alignment

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2 Skipped Deployments

Project	Deployment	Review	Updated (UTC)
hashdotdesign	Ignored	Preview	Jan 26, 2026 0:43am
hashdotdesign-tokens	Ignored	Preview	Jan 26, 2026 0:43am

[augmentcode]

🤖 Augment PR Summary

Summary: Aligns @hashintel/ds-theme and its internal consumers to version 0.0.0 (plus lockfile updates).
Why: Prepares the package for publication so it can be consumed outside the monorepo via the Changesets release flow.

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[augmentcode]

Review completed. 2 suggestions posted.

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