feat(ui-drilldown,ui-options,ui): rework Drilldown

[ToMESSKa]

INSTUI-4792

ISSUE:

• Drildown needs to be migrated to the new theming system

TEST PLAN:

• check if the component works the same as before in v1
• check if the components and the examples work in v2 (especially the dark theme)
• check if all necessary the imports are renamed to latest in v2
• check if the test files are removed from the v1
• check if the right imports are used in exports/b.ts and exports/a.ts
• check if the package.json uses the correct versioning
• check if the renamed or removed tokes are documented in the upgrade guide
• check if the index.ts files use withStyle instead of withStyleLegacy
• check if the v2 component uses all the tokens
• see this link to see the rework: https://instructure.design/pr-preview/pr-2469/v11_7/Drilldown
• check if the tokens are displayed in Drilldown and its sub-component properly in v111_6 and v11_7

[ToMESSKa]

Drilldown displays the token of Options in some of its subcomponents, so I implemented this functionality without the theme.ts files like in v11_6

[github-actions]

PR Preview Action v1.8.1
🚀 View preview at https://instructure.design/pr-preview/pr-2469/
Built to branch gh-pages at 2026-03-18 08:23 UTC. Preview will be ready when the GitHub Pages deployment is complete.

[matyasf]

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[matyasf]

Can you please write about the token changes in the upgrade guide? While the Drilldown tokens itself havent changed, its using other components which did, so just a sentence like "Drilldown.Option is an Options.Item, Drilldown.Separator an Options.Separator under the hood, so token the token changes are the same"

Otherwise it looks good, nice work!