Create dedicated CfP landing page

[t-redactyl]

Adding content to make a dedicated landing page for the CfPs with additional information. This page will provide a link for users to go through to the CfP Pretalx page.

Outstanding questions:

• Have I made the correct changes to links.json so that this page will now replace the current "Call for Proposals" page under "Programme" on the site?
• Do I need to delete the current programme page link, or is it fine to leave it?
• Is there a way to get the links to the CfP Pretalx page to appear as a button? I just have them as links right now but it would be nice if they stood out more.

[hypha]

Thanks Jodie! Some wee comments to a very nice page!

In addition, I wonder if it is helpful to link to /tracks, /selection process, and maybe even /mentorship somewhere so that all CfP related information are referenced here (totally OK if we don't though!)

As for the questions:

1. indeed, no change is needed for the links.json.
2. I do believe you need to delete the cfp.astro file to remove the redirect: https://github.com/EuroPython/website/blob/ep2025/src/pages/programme/cfp.astro. Then when cfp.mdx exists, it will go there.
3. the button syntax is added as a suggestion in place.

[t-redactyl]

Accepted all of the changes (thank you for updating the button!) and replied to the comments.

[t-redactyl]

I've added the requested changes @hypha - let me know if it looks good to go!

[hypha]

Looks great to me! Thank you so much!
Maybe @cybit, @egeakman or @cmaureir wants to merge unless there are further feedback?

[cybit]

I know it's not the proper, proper form to have spaces before and after an em-dash. But I do prefer the space because it breaks up the words instead of connecting them and I'm not sure if the browsers do line-breaks correctly when there is no space. And if TTS-readers are all able to detect that there are two words.