fix(landingpage): routing of shared storybook links doesn't work

[TobiasHeimGalindo]

Closes #1156

Notes:

Ever since I added the selectedVersion dropdown, the iframe will default to the welcome page (https://elements.inovex.de/version/${selectedVersion}/?path=/story/docs-welcome--page)

to prevent this defaulting on each refresh the correct path is now extracted from the initial URL and constructed in the iFrameUrl useMemo. The useStorybookUrl.ts and useStorybookUrlSyncer.ts were okay

[MariaLStefan]

I still get this error when i want to access a page via url paste. I fixed this in #1131 ...
Did something break, or am I the only one who gets this error?

Error: The provided href (/[lang]/library/en) value is missing query values (lang) to be interpolated properly. Read more: https://nextjs.org/docs/messages/href-interpolation-failed

[TobiasHeimGalindo]

@MariaLStefan as mentioned in the bi-weekly, the href lang error is an on going error in the dev mode not caused by this ticket.