dev server: handle hmr and css importer persistence

[thejackshelton]

On HMR reload (still initial render), css imports are losing their persistence. Currently top level css imports think they are not top level after an hmr refresh, this set keeps track of that.

What is it?

• Bug

Description

Checklist

• My code follows the developer guidelines of this project
• I performed a self-review of my own code
• I added a changeset with pnpm change
• I made corresponding changes to the Qwik docs
• I added new tests to cover the fix / functionality

[changeset-bot]

🦋 Changeset detected

Latest commit: 6ea203c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 4 packages

Name	Type
@builder.io/qwik	Patch
eslint-plugin-qwik	Patch
@builder.io/qwik-city	Patch
create-qwik	Patch

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Click here if you're a maintainer who wants to add another changeset to this PR

[pkg-pr-new]

Open in Stackblitz

npm i https://pkg.pr.new/@builder.io/qwik@7389

npm i https://pkg.pr.new/@builder.io/qwik-city@7389

npm i https://pkg.pr.new/eslint-plugin-qwik@7389

npm i https://pkg.pr.new/create-qwik@7389

commit: 0c90802

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PR Overview

This PR fixes a bug where CSS imports lose their persistence after an HMR reload by tracking CSS importers more accurately.

• Updated the changeset to indicate a patch release.
• Introduced a new Set to track CSS importers post-HMR reload.
• Modified the injection logic by ensuring CSS files imported by CSS are not redundantly re-injected.

Reviewed Changes

File	Description
.changeset/quiet-flowers-divide.md	Updates changeset with release note for the patch.
packages/qwik/src/optimizer/src/plugins/vite-dev-server.ts	Adds logic to track and check CSS importers to maintain HMR persistence.

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

packages/qwik/src/optimizer/src/plugins/vite-dev-server.ts:90

• [nitpick] The variable name 'cssImportedByCSS' is somewhat ambiguous. Consider renaming it to a more descriptive name such as 'persistentCssImports' to clearly convey its purpose.

const cssImportedByCSS = new Set<string>();

[Varixo]

Lgtm

[wmertens]