feat: add source name logging to $inspect.trace

[Ocean-OS]

This adds name logging to $inspect.trace. Currently, $inspect.trace logs the type of dependency ($state or $derived), its current value, and a few stack traces related to it. In this PR, to better understand your dependencies, it includes the name of each dependency— if it's a variable, it'll log its name, and if it's an object property, it'll log the path (eg object.foo.bar.baz[0]).

Probably closes #15954

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[changeset-bot]

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Latest commit: 0901a1b

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Playground

pnpm add https://pkg.pr.new/svelte@16060

[Rich-Harris]

What does PROXY_REMOVE_PATH do? No tests fail if I remove it altogether

[Ocean-OS]

It does the [$state proxy] tag when a proxy is shared by two sources

[Ocean-OS]

I don't think there's any tests for that yet

[Ocean-OS]

Also, is there any reason you removed the proxy version source tag?

[Rich-Harris]

No, just commented it out to understand better, but then forgot to uncomment

[Ocean-OS]

I just realized we should probably tag the sources used in svelte/reactivity
I'll do that later today