[Assistants] trending feature (#938)
* [Assistants] trending feature
* cleaner sort query
* create & use `AssistantStats` collection
* fix grouping
* rm usage of migration
* ♻️ Refacto lock usage / AssistantStat
* 🩹 Fix last24HoursCount.count => last24HoursCount
* 🐛 Fix collection name
* 🐛 Fix DB query
* 🐛 Fix rate limit on assitant creation
* 🐛 Fix aggregation query
* ✨ Only run refreshAssistants if assistants are enabled
* hide UI until we have enough stats collection
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Co-authored-by: coyotte508 <coyotte508@gmail.com>
