chore: runtime linting

[dummdidumm]

• check that the runtime doesn't use methods that are too new
• add linting rule to prevent references to the compiler in the runtime (this is important for the first check, else the ambient node typings would be included, which includes a definition for at(), which means we no longer would get errors when violating the "don't use new methods" rule in the runtime)
• fix code as a result of these new checks

closes #10438

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• Ideally, include a test that fails without this PR but passes with it.

Tests and linting

• Run the tests with pnpm test and lint the project with pnpm lint

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Latest commit: 35439f1

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[dummdidumm]

(first lint should fail now, let's see if this works in CI as well. Update: yes it worked)