chore(typecheck): typescript is the tsc-rs drop-in, no effect-tsgo patch - #23023

Eligibility
This is a development-toolchain migration to the @tsc-rs/typescript drop-in, with corresponding script, dependency, lockfile, and documentation updates. Its effects are limited to installation, editor, typecheck, and test tooling, with no product-runtime or product-default changes.

Notes:
No code owners found in target merge base a12d6ed

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