Description

• Fixes Fix create tag autofocus modular-learning#265
• Fixes Frontend max taxonomy depth should match backend modular-learning#269

Note on unit testing

I have decided against additional unit tests because:

• The constant is designed to be adjustable, I don't think we need to expect it to be a specific value
• The autofocus bug was due to an unfortunate last-minute addition by copilot, which slipped through my review. Since it's a random line of code that I don't expect to resurface, I don't see any danger of regression that we should test against.

I have no strong opinion on this whatsoever. If you want tests, let me know and I'll write tests.

Testing instructions

• Go to a taxonomy

• Create nested subtags 6 levels deep (count from top to innermost tag - sum should be 6 levels)

• You should not encounter an error

• All levels should have an expand/collapse icon and a menu with Add Subtag and Rename actions

• Only on the innermost level (that should be the 6th level) the Add Subtag action should be disabled

• Reload page

• New tags now appear alphabetically ordered (they have been refreshed from server)

• You should see all 6 levels on expanding them

• Innermost level (6th level) should have the Add Subtag action disabled and should not have a collapse/expand icon

• Create any new tag

• Autofocus should automatically move the cursor to the input field

• type in any single character

• that character should not be highlighted

• type in more characters

• since the first character was not highlighted, new character should not overwrite previous one

Best Practices Checklist

We're trying to move away from some deprecated patterns in this codebase. Please
check if your PR meets these recommendations before asking for a review:

• Any new files are using TypeScript (.ts, .tsx).
• Avoid propTypes and defaultProps in any new or modified code.
• Tests should use the helpers in src/testUtils.tsx (specifically initializeMocks)
• Do not add new fields to the Redux state/store. Use React Context to share state among multiple components.
• Use React Query to load data from REST APIs. See any apiHooks.ts in this repo for examples.
• All new i18n messages in messages.ts files have a description for translators to use.
• Avoid using ../ in import paths. To import from parent folders, use @src, e.g. import { initializeMocks } from '@src/testUtils'; instead of from '../../../../testUtils'