Replace the tsgo native preview with typescript@7.0.2 and port the check scripts to the TS 7 API. Target ES2024, drop useDefineForClassFields: false and unused decorator options, and enable verbatimModuleSyntax. Replace tsx with node plus the source resolver hook, passed to --import as a file URL.
closes#9965
On macOS tmpdir() is a symlink (/var -> /private/var) while the spawned
CLI's process.cwd() is physical, so session cwd filtering never matched
the fixtures and the fork-target rejection test failed locally.
