Make compatible with Svelte 5

[watzon]

Describe the bug
Attempting to use in a Svelte 5 project with runes enabled results in the following error:

✘ [ERROR] node_modules/svelte-seo/index.svelte:3:2 Cannot use `export let` in runes mode — use `$props()` instead [plugin vite-plugin-svelte:optimize-svelte]

    node_modules/svelte-seo/index.svelte:3:2:
      3 │  export let title = undefined;
        ╵   ^

  The plugin "vite-plugin-svelte:optimize-svelte" was triggered by this import

    node_modules/svelte-seo/index.js:1:22:
      1 │ import component from "./index.svelte";
        ╵                       ~~~~~~~~~~~~~~~~

To Reproduce
Steps to reproduce the behavior:

1. Install in a Svelte 5 project
2. Use as described in docs

Expected behavior
It should work.

Desktop (please complete the following information):

• OS: macOS
• Browser: Chrome

[lubiah]

Hi @watzon ,
Is there a way to check the current svelte version with code?
I think the solution is to use an if statement and use different code for svelte 5

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Shackless]

I'd like to reopen this as Svelte 5 is officially released now.

[lubiah]

@Shackless , I'd take a look at this

[lubiah]

@artiebits , can we re-open this issue, I would like to migrate the project to use $props instead of the let

[chanmathew]

Hi folks, I'm running into issues also with Svelte 5. @artiebits would you mind taking a look and merging the PR?