fix: default values in object destructuring

[caiquetorres]

This PR addresses an issue where destructuring objects and arrays within an each block causes the compiler to break if the default value of a property contains a string with special characters like } or ]. The current validation logic does not correctly handle these cases and incorrectly interprets such characters when they are inside strings.

Additionally, the solution includes support for template string syntax, ensuring these are also handled appropriately.

Resolves #12131

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Tests and linting

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

[changeset-bot]

🦋 Changeset detected

Latest commit: bfe3b71

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

This PR includes changesets to release 1 package

Name	Type
svelte	Patch

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[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14554-svelte.vercel.app/

this is an automated message

[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14554

[Ocean-OS]

To fix the failing lint test, run Prettier on your changed files.

[Rich-Harris]

thank you!