Add documentation for Anki integration

[lfavole]

Proposed change

This PR adds the documentation for the Anki integration.

Type of change

• Spelling, grammar or other readability improvements (current branch).
• Adjusted missing or incorrect information in the current documentation (current branch).
• Added documentation for a new integration I'm adding to Home Assistant (next branch).
  • I've opened up a PR to add logos and icons in Brands repository.
• Added documentation for a new feature I'm adding to Home Assistant (next branch).
• Removed stale or deprecated documentation.

Additional information

• Link to parent pull request in the codebase: Add Anki integration core#148748
• Link to parent pull request in the Brands repository: Add Anki integration icons brands#7462
• This PR fixes or closes issue: fixes #

Checklist

• This PR uses the correct branch, based on one of the following:
  • I made a change to the existing documentation and used the current branch.
  • I made a change that is related to an upcoming version of Home Assistant and used the next branch.
• The documentation follows the Home Assistant documentation standards.

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[c0ffeeca7]

🎉

[lfavole]

Actually I forgot to uncheck that checkbox...

Then, as you said, I created my branch from the current branch (because there were no other branches in my fork), but I created my pull request on the next branch.
GitHub was displaying that it was directed to the next branch, which was even more confusing...

I will remember it for the next time 😂

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

Learn more about our pull request process.

[c0ffeeca7]

Actually I forgot to uncheck that checkbox...

Then, as you said, I created my branch from the current branch (because there were no other branches in my fork), but I created my pull request on the next branch. GitHub was displaying that it was directed to the next branch, which was even more confusing...

I will remember it for the next time 😂

Ah I see! Yeah, that's confusing. And easy to miss that checkbox.

[c0ffeeca7]

Thank you, @lfavole 👍 Nice first integration docs.

[Copilot]

Pull Request Overview

This PR adds documentation for a new Anki integration that allows Home Assistant users to monitor their flashcard review status. The integration connects to AnkiWeb or custom sync servers to display the number of cards that need to be reviewed.

Key changes:

• Creates comprehensive documentation for the Anki integration with setup instructions and troubleshooting
• Documents three sensor entities for tracking new, learning, and review cards
• Provides configuration details for connecting to AnkiWeb or custom sync servers