✨ Add stats on conversations (#828)
* ✨ Add stats on conversations
* 🩹 Fix conversation stats compute
* ⚡️ Slightly better index
* 🔊
* 🩹 Some fixes
* 🐛 Fix aggregation query
* 🐛 Fix $merge stage of query
* 🐛 Fix query on sessionId
* ✨ Compute weekly/monthly unique users
* 🩹 Final tweaks
* ⚡️ Split aggregations for better perf
No need to recompute DAUs / WAUs and so on
* ♻️ Deprecate PARQUET_EXPORT_SECRET & fix sec vuln
* Add ADMIN_API_SECRET to CD action
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Co-authored-by: Nathan Sarrazin <sarrazin.nathan@gmail.com>
