fix(pluginContainer): run transform in this.load

[bluwy]

Description

Rollup docs: https://rollupjs.org/plugin-development/#this-load

Follow-up from #11469

• Further, this.load is supposed to trigger transform and moduleParsed - this does not (in accordance with vite's on-demand nature)

I think it still make sense to run the transform part. Vite's on-demand nature shouldn't affect plugin container's compatibility with Rollup as long as it makes sense in dev. We do transform in dev, but we don't do moduleParsed, but we should have the code to also support that if we want.

Additional context

I spotted this while working with the Remix folks. It doesn't blocked them or me now, so this would be a nice to have.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[patak-dev]

I think we should merge this one for Vite 5