Session affinity / sticky sessions / cookie based traffic splitting

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Hello, wonderful Knative community!
Thanks for all your effort, I'm a new user who's fascinated by the project you've created.
However, I could not find answer to the question: is it possible to use cookies when splitting traffic to be sure that the same user will always be directed to the same revision?
I know this feature exists in bare Istio, Gloo, ..., but could not find any info how to make use of it in Knative, and whether it is even possible or not.
Thanks!

(i wasnt sure which area to chose, so i left it blank, sorry for the inconvenience)

The issue does not name files, tests, or entry points. Start by reviewing Knative Serving's existing traffic-splitting and routing behavior, then determine whether cookie-based session affinity is supported. Done means either identifying the supported configuration and documenting it, or defining the implementation scope if the capability is missing.

Written by the indexing model from the issue text.