[BUILD-456] feat: Update iframe src when reviewed card changes

[RisingOrange]

We need to update url of the AnkiHub AI page loaded in the iframe when the reviewer switches to a new card. (The urls look like this: https://app.ankihub/ai/chatbot/<note_id>)

• The iframe should load the chatbot page for the currently reviewed note.
• The page should be loaded only when necessary:
  • It should be only loaded if the iframe is visible.
  • The page should not get reloaded when the user re-opens it on the same card.

Related issues

https://ankihub.atlassian.net/jira/software/c/projects/BUILD/boards/1?selectedIssue=BUILD-456

Proposed changes

• Refactor ankihub/gui/web/ankihub_ai.js to use an AnkiHubAI class.
• Add logic for updating the iframe source when necessary to AnkiHubAI.
  • The embedded-auth view is only loaded the first time the chatbot is opened. (This sets a cookie which is used for authentication from then on.)
• Call AnkiHubAI.cardChanged(noteId) (a javascript-method) from the python side when the reviewed card changes.

How to reproduce

• Comment out this code to make it work with any AnkiHub deck: https://github.com/ankipalace/ankihub_addon/blob/1a8b0eb4b3c2b030b0c538c44fea8fc6014e151f/ankihub/gui/reviewer.py#L104-L107
• Enable the chatbot feature flag on your local ankihub web app
• Open an ankihub note in the reviewer
• Follow the steps in the video

Screenshots and videos

https://github.com/ankipalace/ankihub_addon/assets/31575114/98b06ba8-f079-49c0-b658-1db3dd5de941

Comment

We will need to handle the case that the token used for authentication with the chatbot page is invalid. This will be done in a different task: https://ankihub.atlassian.net/jira/software/c/projects/BUILD/boards/1?selectedIssue=BUILD-455

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 87.66%. Comparing base (8f2405a) to head (4f20087).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #978 +/- ## ========================================== + Coverage 87.65% 87.66% +0.01% ========================================== Files 66 66 Lines 6724 6730 +6 ========================================== + Hits 5894 5900 +6 Misses 830 830 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.