fix(nx-plugin): rename Vite config and correct Vitest version for Vitest schematic

[brandonroberts]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/analogjs/analog/blob/main/CONTRIBUTING.md#-commit-message-guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

Which package are you modifying?

• vite-plugin-angular
• vite-plugin-nitro
• astro-angular
• create-analog
• router
• platform
• content
• nx-plugin
• trpc

What is the current behavior?

The setup-vitest schematic/generator installs an incorrect version of Vitest (1.31.1), and uses a vite.config.ts which fails because an existing project is not set to use ESM by default.

Closes #

What is the new behavior?

• The setup-vitest schematic/generator installs the correct version of Vitest (^1.3.1).
• A vite.config.mts file is used instead which uses ESM for Vitest only.
• The ^1.0.0 version of Analog packages is installed.

Does this PR introduce a breaking change?

• Yes
• No

Other information

[optional] What gif best describes this PR or how it makes you feel?

[Micha-Richter]

Do the vite config files in the templates of create-analog also need to be renamed? 🤔

[brandonroberts]

@Micha-Richter no, they don't. This is for the standalone Vitest setup. If you want to migrate completely to Analog, more changes are required, including updating the package.json, angular.json, and possibly renaming vite.config.mts to vite.config.ts. Both filenames will work though. We're using vite.config.mts in this case so Vite resolves it to ESM, because the plugins are ESM-only now. The Angular CLI is still using CommonJS though.

I don't want to force the full update to ESM for existing workspaces as its not as fully tested with the Angular CLI.