Feat: Add read-only binding focused

[RaiVaibhav]

Svelte 5 rewrite

Add new readonly focused binding
Feat: #8949

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.

Tests and linting

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

[changeset-bot]

🦋 Changeset detected

Latest commit: bb4c3e1

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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[RaiVaibhav]

Forgot to run the lint before push, I have forced pushed the changes into one commit.

[RaiVaibhav]

Hey @trueadm can you help me with failing lint, not sure what's the issue, here with CI.

[RaiVaibhav]

🤯 entire code just changed with flush and listen, feels like I did a lot of mistakes, a lot 😅

[Rich-Harris]

thank you! starting the PR is the hard part, the rest is just minor details :)