[Mongo] count messages (aggregate) only when needed (#863)
* [Mongo] count messages (aggregate) only when needed
* more restrictive
* even more stricter
* Update src/routes/+layout.server.ts
Co-authored-by: Eliott C. <coyotte508@gmail.com>
* format
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Co-authored-by: Eliott C. <coyotte508@gmail.com>