[wip] Replace LegacyHidden with Activity mode#32507

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rickhanlonii wants to merge 2 commits intofacebook:mainfrom rickhanlonii:rh/legacy-hidden-activity

+343-32

Commits on Mar 2, 2025

[refactor] Add element type for Activity
rickhanlonii
committed

Commits on Mar 3, 2025

[internal] add activity mode for legacy hidden
rickhanlonii
committed