fix: respect optimize deps entries

[patak-dev]

Description

Once we merged:

• feat: scan free dev server #8319

We stopped respecting optimizeDeps.entries. This PR uses this config option to let users be explicit about which extra entries should be processed before the first deps optimization step.

Right now, the optimization is run after every static import (+ dynamic imports that are triggered by the browser while loading the first visited page) are processed. This seems like a good default because processing every dynamic import may be more costly now that we don't do it with the esbuild scanner, especially for apps like StoryBook-like apps.

After this PR, the user should add to entries every dynamic import entry that is commonly used after the first load.

TODO: Tests.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

[patak-dev]

The PR now includes a refactor to move the delay until idle logic from the optimizedDeps plugin inside DepsOptimizer (another step in having a single place to control this logic). We need this now because we should process the optimizeDeps.entries only on cold start.

With the logic in DepsOptimizer, we could implement in another PR that we always start a new delay until idle instead of only doing it the first time and then falling back to the old debounce. Every time there is a new dynamic import, it would be better to until all new sources have been processed.

[bluwy]

One small nitpick, but great refactor overall!