refactor: rewrite .js imports in scripts folder to .ts

[Mrtenz]

Explanation

In preparation for dropping the tsx dependency, I've updated all .js imports to .ts imports in the scripts folder. We may eventually want to do this in the packages too, but to keep this pull request small, I skipped that for now.

Also updated some scripts from .mts to .ts as .mts is not needed anymore now that the entire workspace is ESM.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Low Risk
Tooling-only refactor in CI scripts and dev configs; runtime product code and package import rules are unchanged.

Overview
Prepares the repo to eventually drop tsx by standardizing how scripts/ is written and invoked.

Script entrypoints that used .mts are renamed to .ts (e.g. get-changed-workspaces, lint-tsconfigs, close-stale-release-prs, shared scripts/lib/workspaces). GitHub Actions, root package.json, yarn.config.cjs, and every workspace lint:tsconfigs script are updated to call the new paths.

Relative imports under scripts/ switch from .js / .mjs specifiers to .ts. tsconfig.base.json enables allowImportingTsExtensions, while tsconfig.packages.json explicitly turns it off so published packages stay unchanged. oxlint.config.ts adds an import/extensions override for scripts/**/*.ts, and suppression keys are retargeted to the renamed files.

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[Mrtenz]

Added this here instead of tsconfig.scripts.json since this is what the IDE uses. If we only add it to tsconfig.scripts.json, you would see a bunch of TypeScript errors in your IDE.

[Mrtenz]

Overriding the new option in tsconfig.base.json.