Remove NPM install from frontend configuration

[davidfowl]

Description

Default is now npm install.

Checklist

• Is this feature complete?
  • Yes. Ready to ship.
• Are you including unit tests for the changes and scenario tests if relevant?
  • No
• Did you add public API?
  • No
• Does the change make any security assumptions or guarantees?
  • No
• Does the change require an update in our Aspire docs?
  • No

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/dotnet/aspire/main/eng/scripts/get-aspire-cli-pr.sh | bash -s -- 12542

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/dotnet/aspire/main/eng/scripts/get-aspire-cli-pr.ps1) } 12542"

[davidfowl]

/backport to release/13.0

[github-actions]

Started backporting to release/13.0: https://github.com/dotnet/aspire/actions/runs/18961675149

[Copilot]

Pull Request Overview

This PR removes an unnecessary .WithNpm(install: true) call from the Python starter template's Vite app configuration.

• Simplifies the template code by removing redundant configuration

[eerhardt]

This happened in #12530. Closing.