fix: update resolution logic for vp create to match npm-init (#1041)

Updates the resolution logic of `vp create` to match the logic from
[`npm-init`](https://docs.npmjs.com/cli/v11/commands/npm-init),
specifically around scoped names without a package. With `npm create`
and `pnpm create`, scoped named resolve to `@scope/create`.

Ran into this trying to run `vp create @scope` and got hit with a
confusing error message, so figured I'd just upstream a fix!

---------

Co-authored-by: MK (fengmk2) <fengmk2@gmail.com>

Author: rrdelaney

packages/cli/src/create/__tests__/discovery.spec.ts

@@ -60,8 +60,10 @@ describe('expandCreateShorthand', () => {
     expect(expandCreateShorthand('/absolute/path')).toBe('/absolute/path');
   });
 
-  it('should handle scope-only input gracefully', () => {
-    expect(expandCreateShorthand('@scope')).toBe('@scope');
+  it('should expand scope-only input to @scope/create', () => {
+    expect(expandCreateShorthand('@scope')).toBe('@scope/create');
+    expect(expandCreateShorthand('@scope@latest')).toBe('@scope/create@latest');
+    expect(expandCreateShorthand('@scope@1.2.3')).toBe('@scope/create@1.2.3');
   });
 
   it('should handle special cases where default convention does not apply', () => {

packages/cli/src/create/discovery.ts

@@ -169,7 +169,11 @@ export function expandCreateShorthand(templateName: string): string {
   if (templateName.startsWith('@')) {
     const slashIndex = templateName.indexOf('/');
     if (slashIndex === -1) {
-      return templateName;
+      // @scope or @scope@version → @scope/create[@version]
+      const atIndex = templateName.indexOf('@', 1);
+      const scope = atIndex === -1 ? templateName : templateName.slice(0, atIndex);
+      const version = atIndex === -1 ? '' : templateName.slice(atIndex);
+      return `${scope}/create${version}`;
     }
     const scope = templateName.slice(0, slashIndex);
     const rest = templateName.slice(slashIndex + 1);