> Which is to say: is there some obvious hook-point to add watcher jobs (as Clickhouse stored procedures, maybe?) to process correlations in the inputs to the system? (Where by "watcher jobs", I mean things like "create a record in a table if a user makes requests across endpoints A, B, C, in that order — with other arbitrary requests from that user in between — in a five-minute sliding window, at some point within 12 hours of the user's registration.")

This is not something we have planned, nor have we heard yet. Is the use case for doing analytics on your web application? Or more of a complex tracing use case that creates new traces as time passes by?

Fwiw, Highlight is designed (in the current state) for basic log search and alerts.