Slate v2 Package Readme Truth Pass

Goal

Replace stale boilerplate package front doors with short current-surface readmes.

Completed

• updated packages/slate/Readme.md
• updated packages/slate-react/Readme.md
• updated packages/slate-history/Readme.md

Each readme now names:

• the current package role
• the current public surface
• the current proof/test lane

Verification

• readback of the touched package readmes
• yarn lint:typescript