Add new index definitions for various collections in hub-20-04-2026.txt

[KilianBoute]

Description

Why

Several high-traffic collections were missing explicit index definitions or relied on implicit/default indexing. As data volume grows, this leads to slower queries, higher CPU usage, and increased risk of performance regressions that are hard to detect late.

What this improves

This PR adds a complete, explicit set of index definitions for all relevant Hub collections, aligned with real query patterns (organisation, user, time-based, and compound lookups). Making indexes explicit:

• Improves read performance and query predictability
• Reduces full collection scans under load
• Documents the intended access patterns in version control
• Makes schema and performance changes auditable and repeatable across environments

Overall, this strengthens database performance, scalability, and operational reliability.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!