[#4193]: upgrade typescript

[oakenroot]

Summary of the changes

Upgrades typescript to 5.8 across the board, which is a blocker on #4205. I have gone for 5.8 here, but can go for 5.2 if that's preferable. 5.8 is the highest we can go right now, because 5.9 introduces autocorrect: boolean on HTMLElement which conflicts with ours, which do autocorrect: "on" | "off".

This also makes changes to docs, which popped up when running npm run build to check everything is happy. I assume these should have been updated in previous PRs. Happy to drop the commit from here and put on a separate PR if people like.

Related issue

#4193

Checklist

General

• Changes to docs package checked and committed.
• All acceptance criteria reviewed and met.

Testing

• Relevant unit tests and visual regression tests added.
• Visual testing against Figma component specification completed.
• Playground stories in React Storybook up to date, with any prop changes and additions addressed.
• Compare performance of modified components against develop using Performance addon in React Storybook.

Accessibility

• Accessibility Insights FastPass performed.
• A11y unit test added and yields no issues.
• A11y plug-in on Storybook yields no issues.
• Manual screen reader testing performed using NVDA and VoiceOver.
• Manual keyboard testing for keyboard controls and logical focus order.
• Correct roles used and ARIA attributes used correctly where required.
• Logical heading structure is maintained, and the HTML elements used for headings can be changed to fit within the wider page structure.

Resize/zoom behaviour

• Page can be zoomed to 400% with no loss of content.
• Screen magnifier used with no issues.
• Text resized to 200% with no loss of content.
• Text spacing increased as per the WCAG 1.4.12 success criterion with no loss of content.

System modes

• Browser setting 'prefers reduced motion' tested. No animations or motion visible whilst this setting is on.
• Windows High Contrast mode tested with no loss of content.
• System light and dark mode tested with no loss of content.
• Browser support tested (Chrome, Safari, Firefox and Edge).

Testing content extremes

• Min/max content examples tested with no loss of content or overflow.
• All prop combinations work without issue.
• Tested for FOUC (Flash of Unstyled Content) in both SSR (Server-Side Rendering) and SSG (Static Site Generation) settings.
• Controlled and uncontrolled input components tested.
• Props/slots can be updated after initial render.

[oakenroot]

I now have follow up branches to this to solve #3857 and #4205, which both seem to be working nicely locally. Have pushed these to my fork, eg https://github.com/oakenroot/ic-ui-kit/tree/chore/4205-upgrade-lerna. I can PR these in sequence once this merges, but can't stack as I can't create branches directly on this repo.

There are more likely more dependency/audit bits to do after bumping lerna, but will leave for now in case major changes are needed to any of this.

[oakenroot]

Ok, as it turns out I've had a go at removing vulns, and have managed to get down to 2 advisories. Not run much manual testing but all validation and unit testing is passing locally...

[GCHQ-Developer-530]

Hi @oakenroot, I don't seem to get those docs changes if I build locally, not sure on other members of the team. Please could you drop the commit from this PR anyway and then it can be looked into in a separate PR as you suggested?

[GCHQ-Developer-299]

heya @oakenroot, thank you for another contribution :) unfortunately due to our commitlint setup, you'll need to separate the changes to each package into separate commits (e.g. /canary-react changes into a chore(canary-react):... commit)

[oakenroot]

Alright, have dropped the docs commit and split up the version bumps, should be good now... :)