Delineate between daily / annual limit csv validation

[whabanks]

Summary | Résumé

This PR adds a distinction between daily and annual limits when validating whether the length of a CSV will exceed the service's message limit.

Related Issues | Cartes liées

• Validate annual limits on message send notification-api#2375

Test instructions | Instructions pour tester la modification

• CI passes
• Existing bulk send functionality is intact
• Errors still throw when going over the daily limit with a larger send
• Can still perform bulk sends in general

Release Instructions | Instructions pour le déploiement

None.

Reviewer checklist | Liste de vérification du réviseur

• This PR does not break existing functionality.
• This PR does not violate GCNotify's privacy policies.
• This PR does not raise new security concerns. Refer to our GC Notify Risk Register document on our Google drive.
• This PR does not significantly alter performance.
• Additional required documentation resulting of these changes is covered (such as the README, setup instructions, a related ADR or the technical documentation).

⚠ If boxes cannot be checked off before merging the PR, they should be moved to the "Release Instructions" section with appropriate steps required to verify before release. For example, changes to celery code may require tests on staging to verify that performance has not been affected.