Decommissioning the quantum cloud

[doctorperceptron]

This PR updates the sections in the docs relevant to cloud hardware access. Some sections are removed, and warnings are added indicating that cloud access is no longer available.

[heltluke]

I guess there are a number of broken links now? Not sure the best way to go about stomping them all out. Are we going to publish the new docs on RTD as well?

[doctorperceptron]

I guess there are a number of broken links now? Not sure the best way to go about stomping them all out.

No, this PR removes all the links to strawberryfields.ai. I've spent some time combing through to make sure I got them all. Wouldn't mind an extra pair of eyes though! 👀

Are we going to publish the new docs on RTD as well?

That's the plan. Looks doable without creating a release. I've reached out to Rashid for help with this.

[heltluke]

I've spent some time combing through to make sure I got them all. Wouldn't mind an extra pair of eyes though! 👀

I was referring to the errors in the "Documentation check / sphinx" action: https://github.com/XanaduAI/strawberryfields/actions/runs/21044628201/job/60515434450?pr=763

[doctorperceptron]

I was referring to the errors in the "Documentation check / sphinx" action: https://github.com/XanaduAI/strawberryfields/actions/runs/21044628201/job/60515434450?pr=763

Ah good catch, missed those.

[doctorperceptron]

@heltluke got most of them. I don't want to touch any code files, so can't get them all. The nice thing about Sphinx is that for any links it can't find, it just won't create a hyperlink but will retain the original text, so we won't have dead links, just plain text with no link.