ci(renovate): pin vite-plugin-dts to <5 pending moduleResolution migration

[mdeliatf]

Description

vite-plugin-dts v5 splits its implementation into a separate unplugin-dts package and exposes types exclusively via package.json exports subpaths. That requires TypeScript's moduleResolution to be node16, nodenext, or bundler, but this project still uses classic node resolution (see the @ts-expect-error markers in vite.config.ts). The result is a TS1192: Module 'vite-plugin-dts' has no default export error in vite.config.ts under v5.

This PR adds a Renovate packageRules entry pinning vite-plugin-dts to <5.0.0 until the moduleResolution migration lands, alongside an inline comment explaining the constraint and the unlock condition.

Related to #5156

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