Adds multiple accessibility fixes

[nhsbsa-mamcp]

Multiple accessibility fixes based on what is present in the Data Science Playbook. These were done in tandem with a full accessibility review, so should address all or almost all issues in this playbook.

• Disable site search - it introduces an accessibility error in Wave no matter how it is configured
  • overlay gives empty button
  • textbox gives empty label
• logo naming and config - matches requirements in our accessibility checklists, Manual Checklist (MC) 20 and Screen Reading (SR) 1
• collapse: false - this controls whether the navbar collapses to a burger menu under certain page width, but the implementation quarto provides is not accessible due to missing aria attributes
• text: Playbook Home Page - just distinguishes from another 'Home' link on right side of navbar
• page-footer - added as a place for link to accessibility statement; statement required by law for all websites
• image-alt - images must have an alt-text attribute according to WCAG
• skip-link - JS script to add a 'skip-link' to all pages, as per MC4
• post-load-accessibility-fixes - includes 2 fixes
  • quarto dynamically inserts 2 tags into pages, with aria-hidden attribute; however, these are focusable which is not accessible, so we set the tabindex to -1 to prevent focusing
  • quarto adds an aria-expanded attribute to callout elements, which is not accessible; hence we remove these from initial DOM and whenever they are added back

[nhsbsa-alijo]

The changes look good - no specific comments.

But could you provide a list of what this should mean from a user perspective so I can test please?

Can I also double check: do we need to keep the ticket open once this is merged? Will there be changes relating to accessibility in the stats playbook that we want to integrate, or does this PR cover everything? Might be one to check with @MWilson92

Thanks!

[nhsbsa-mamcp]

But could you provide a list of what this should mean from a user perspective so I can test please?

Added to PR opening comment

Can I also double check: do we need to keep the ticket open once this is merged? Will there be changes relating to accessibility in the stats playbook that we want to integrate, or does this PR cover everything? Might be one to check with @MWilson92

I will not merge this until @MWilson92 confirms whether there is more to be added to the PR

[nhsbsa-mamcp]

The changes look good - no specific comments.

But could you provide a list of what this should mean from a user perspective so I can test please?

Can I also double check: do we need to keep the ticket open once this is merged? Will there be changes relating to accessibility in the stats playbook that we want to integrate, or does this PR cover everything? Might be one to check with @MWilson92

Thanks!

Hi @MWilson92 - anything you want to include in the PR? Or better to just merge and then open a new one if anything further is needed to bring it in line with the stats playbook?