feat(hmr): check boundary outside the circular imports

[sapphi-red]

When a HMR boundary is detected within a circular import chain, skip it and continue propagation outward to find a boundary outside the chain.

graph LR
    B["b.js"] -->|import| C["c.js (boundary)"]
    C -->|import| B
    A["a.js (boundary)"] -->|import| B

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When c.js is changed, c.js is now ignored and a.js is now treated as the boundary.

fixes #16580
fixes #18217

[bluwy]

Can you explain this part and why this PR is removing the warning on the client-side? isWithinCircularImports was introduced for #15118 so we reload the page in case the circular modules cannot recover in the client, does that not happen in this PR anymore?

[sapphi-red]

It doesn't happen anymore. If there's a circular import, this PR will make Vite to pick a boundary outside of the circular import. If there's no boundary outside the circular import, it'll trigger a reload. So there won't be a client side error caused by circular imports.

[bluwy]

I see. So a minor difference I think is that as you mentioned, if:

1. There's a boundary in a circular import
2. There's no boundary outside of the circular import

It will now always reload the page. Previously it would try doing an inner boundary HMR first, before falling back to reload.

So, I don't know how Linear's import structure works, but if they have something like index.html -> main.ts -> App.tsx -> ... -> App.tsx, then I assume this will now always trigger a reload, which isn't something they want to happen.

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I'm happy to try the force reload instead so that the execution order is always correct, but if we have a request for the previous behavior again, maybe we need to bring the handling back.