chore: TS fixes cleanup

[dummdidumm]

• move a test
• revert seemginly unnecessary code changes (@Rich-Harris why were those necessary? Was it maybe necessary prior to fix: remove unwanted properties from both replaced and unreplaced nodes #14744, i.e. battling symptoms rather than the cause?)
• adds a test that fails without fix: remove unwanted properties from both replaced and unreplaced nodes #14744

[changeset-bot]

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Latest commit: a7dc546

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[github-actions]

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pnpm add https://pkg.pr.new/svelte@14750