Categories in log stream

[katrin-freihofner]

Summary of the problem (If there are multiple problems or use cases, prioritize them)
With the new user flow, discussed in this issue, we need to explore new ways to show categories besides the anomaly view. One way is, to have categories as part of the log stream.

[elasticmachine]

Pinging @elastic/observability-design (design)

[katrin-freihofner]

After investigating this issue, we decided to keep the categories tab for now.
Design files for future reference
Prototype 1
Prototype 2