fix(npx): route unknown packages directly via npx, not npm run

[NEOFIT-dev]

Problem

rtk npx vue-tsc --noEmit was calling npm run vue-tsc --noEmit instead of npx vue-tsc --noEmit, producing npm error Missing script: "vue-tsc".

Root cause: the default Commands::Npx handler called npm_cmd::run() which injects run before any argument not found in NPM_SUBCOMMANDS. Since vue-tsc is not in that list, it became npm run vue-tsc.

Note: rtk npx vue-tsc --version appeared to work by accident — npm silently consumes --version as its own flag rather than passing it to the script.

Fix

Add npm_cmd::run_npx() that calls npx <args> directly without any run injection, and use it as the default handler for unknown packages in Commands::Npx.

Testing

# Before (system rtk 0.35.0)
$ rtk npx vue-tsc --noEmit
npm error Missing script: "vue-tsc"

# After
$ rtk npx vue-tsc --noEmit
Version 6.0.2
tsc: The TypeScript Compiler - Version 6.0.2
...

Fixes #1269

[CLAassistant]

All committers have signed the CLA.

[KuSh]

Closing as #1458 already fixed the problem