fix(create): inline generator dependencies without catalog support

[SaKaNa-Y]

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Problem

In an npm monorepo, running vp create vite:generator --directory tools/gen --no-interactive creates the generator but fails to install its dependencies:

EUNSUPPORTEDPROTOCOL
Unsupported URL Type "catalog:": catalog:

Subsequent npm install commands also fail. The generator template declares @types/node and typescript as catalog:, and scaffolding copies those declarations without checking whether the selected package manager supports catalogs.

Fix

Use the existing package-manager capability check when scaffolding a generator. For managers without catalog support, replace the template's catalog references with dependency ranges from the bundled monorepo catalog. Catalog-capable workspaces keep their existing references.

This restores dependency installation without duplicating version constants. The installation-failure reporting tracked in #2453 and #2543 remains separate.

Verification

• Regression tests fail before the fix and pass afterward for npm, Yarn 4.9 and pnpm 9.4. Additional cases verify catalog preservation for supported pnpm, Yarn and Bun versions.
• Full unit suite: 1,214 passed, 1 skipped. Formatting, lint and type checks passed.
• cargo test -p vp_cli_snapshots --offline -- create_generator: 3 cases passed, covering npm installation, the existing pnpm generator workflow and rejection outside a monorepo.
• Manual npm workflow: after scaffolding, dependency installation and the generated executable's --help both succeed.

The full CLI snapshot suite was not run; CLI verification covered the three generator cases above.

[SaKaNa-Y]

When running vp create vite:generator in an npm-managed monorepo, the files are generated successfully, but the subsequent dependency installation fails because the generated package.json contains catalog: dependency references, which npm does not support. Running npm install manually afterward fails for the same reason.