Remove saved groups functionality from TK backend

Clare Mingrequested to merge
T429959/remove-saved-groups into main

What?

This MR makes parseWikis resolve an experiment's phase's wikis from its targeting condition alone.

Removed:

  • fetchSavedGroups and the saved_groups_url config it read
  • buildSavedGroupsById and experimentUsesSavedGroups
  • the savedGroupsById context threaded through the validator and adapter
  • the per-experiment cache preservation and conditional drafting that only applied while saved groups were unavailable

The GrowthBook outage handling (preserveAllGb) and the Phabricator alerting added on main are left unchanged.

Why?

Saved groups mapped a GrowthBook saved group ID to a list of wikis so an experiment could target wikis through a referenced group.

This feature is being shelved for now and may be reinstated later. This MR removes it rather than leaving it half-wired into the validation and poll pipeline.

Bug: T429959
Assisted-by: Claude Opus 4.8

Edited by Clare Ming

Merge request reports