ref https://linear.app/tryghost/issue/IPC-66/onboarding-checklist-v1
- Adds a basic version of a new onboarding checklist behind the feature
flag, without incomplete/complete state logic
- Links to Design settings, Members screen and new post
- Opens amodal that we’ll use as Share modal
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Co-authored-by: Daniël van der Winden <danielvanderwinden@ghost.org>
