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

Before submitting the PR, please make sure you do the following

• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
• Prefix your PR title with feat:, fix:, chore:, or docs:.
• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.
• If this PR changes code within packages/svelte/src, add a changeset (npx changeset).

Tests and linting

• Run the tests with pnpm test and lint the project with pnpm lint

[changeset-bot]

🦋 Changeset detected

Latest commit: c6d0db4

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

This PR includes changesets to release 1 package

Name	Type
svelte	Minor

Not sure what this means? Click here to learn what changesets are.

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

[github-actions]

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