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

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: 1123629

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

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

[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.