fix: correctly highlight sources reassigned inside trace

[paoloricciuti]

Alternative to #14801
Closes #14794

This fixes two bugs: one where the sources reassigned in the trace where not properly highlighted and another where the value logged was not correct (it showed the value of the source after the reassignment).

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[changeset-bot]

🦋 Changeset detected

Latest commit: 310d4ba

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

This PR includes changesets to release 1 package

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svelte	Patch

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[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14811-svelte.vercel.app/

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14811

[webJose]

@paoloricciuti hello. I haven't had the time to help out with your request in the other PR, which got closed. I see you opened this new one. Is this new one working on my code? If not, I'll try to check it out today.

[paoloricciuti]

@paoloricciuti hello. I haven't had the time to help out with your request in the other PR, which got closed. I see you opened this new one. Is this new one working on my code? If not, I'll try to check it out today.

It should...maybe if you have some time check out the result to see if it make sense for you too