Reconsider guidelines handling

[nijel]

Describe the problem

The guidelines are calculated when the page is displayed. This makes it slow, as it looks at the string's contents to see if some flags should be applied. This also makes it impractical to display guidelines in other contexts, as they can be super slow on components with hundreds of components (that's why it was removed from billing in f46a074).

Describe the solution you'd like

Calculate them in the background and store the results in the database, doing the calculation only when necessary.

Describe alternatives you've considered

• Keep guidelines standalone; just store them in the database.
• Merge guidelines with alerts and reuse their framework.

Screenshots

No response

Additional context

Alerts are currently for errors, while guidelines are suggestions. This needs to be evaluated to avoid too many annoying alerts.

See also #9497

[github-actions]

This issue has been added to the backlog. It is not scheduled on the Weblate roadmap, but it eventually might be implemented.

In case you need this feature soon, please consider helping or push it by funding the development.

[nijel]

Another issue is poor visibility of guidelines; there is really no reason to navigate to this view once component is configured. This would be helpful in situations like https://github.com/orgs/WeblateOrg/discussions/18883.