fix(create): stop forwarding -- to npx-invoked remote templates (#1421)

Closes #1420.

## Summary

`vp create @tanstack/start` fails with `error: too many arguments for
'create'. Expected 1 argument but got 2.` on npm (reproducible on macOS
and Windows, not platform-specific as originally reported).

## Root cause

`formatDlxCommand` injected `--` between the package name and its args
on the npx path (`npx <pkg> -- <args>`). Per the [npm v8 `npx`
docs](https://docs.npmjs.com/cli/v8/commands/npx), `--` belongs before
the package name; when placed after, npx forwards it to the target
binary. Commander then treats it as end-of-options and promotes
subsequent flags into positional args — exceeding `@tanstack/cli create
[project-name]`'s arity of 1.

Single-entry CLIs (`create-vite`, `create-nuxt`, `sv`) absorbed the
stray `--` harmlessly, which is why this surfaced only after #1238
switched to the Commander-based `@tanstack/cli create`. Fix drops the
`--` from the npx branch; non-npx runners unchanged.

## Verification

Manual smoke in scratch directories with npm and pnpm:

- `vp create @tanstack/start` — TanStack `create` interactive prompt
reached (fix verified for #1420).
- `vp create vite` — `create-vite` prompt reached (blast-radius check).
- `vp create nuxt` — `create-nuxt` prompt reached (blast-radius check).

Author: jong-kyung

packages/cli/src/create/command.ts

@@ -168,10 +168,9 @@ export function formatDlxCommand(
   workspaceInfo: WorkspaceInfo,
 ) {
   const runner = getPackageRunner(workspaceInfo);
-  const dlxArgs = runner.command === 'npx' ? ['--', ...args] : args;
   return {
     command: runner.command,
-    args: [...runner.args, packageName, ...dlxArgs],
+    args: [...runner.args, packageName, ...args],
   };
 }