Use the shared Windows cmd.exe command-line builder for `.cmd` and `.bat` UI runner launches so Node.js v24 no longer sees `spawn(file, args, { shell: true })` and emits DEP0190.
The launcher keeps ordinary `.exe`/`.com` and non-Windows paths on direct argv spawning, while Windows command scripts now run through `cmd.exe /d /s /c` with `shell: false` and `windowsVerbatimArguments: true`.
Local and CI verification passed, including focused UI runner tests, build, check, Real behavior proof, and ClawSweeper gates.
Co-authored-by: Nandana Dileep <nandanadileep@users.noreply.github.com>
Co-authored-by: Brad Groux <3053586+BradGroux@users.noreply.github.com>
