Cross-link resources, accessibility-ready requirements, and make setup resources uniform

[rianrietveld]

The related issue number: #326

This PR adds links to the accessibility-guidelines in topics and link to topic with the guidelines.
I also made the set up of the resources more uniform and fixed some typos and broken links in the docs. And removed some very old, not updated resources.

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• One of the project leads assigned this task to you.
• You did not generate content using AI (artificial intelligence), except for translations or spelling checks.

If you submit code or documentation using a local build:

• Your code builds clean without any errors or warnings while running npm run test.
• You read the documentation in How to contribute to this documentation.
• You checked the modified pages with an accessibility tool like Axe Devtools or WAVE.

[github-actions]

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2026-08-04 10:34 UTC

[rianrietveld]

@amberhinds
I changed the way the resources are setup with the accessibility-ready guidelines.
See the PR preview: https://wpaccessibility.org/pr-preview/pr-389/docs/accessibility-ready/theme-guidelines/
Can you check if this is ok with you?

[GaryJones]

Typo fixes.

[rianrietveld]

@GaryJones Thanks so much for your precise review!