onboarding: Remove feature flag and old welcome crate (#36110)
Release Notes:
- N/A
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Co-authored-by: MrSubidubi <dev@bahn.sh>
Co-authored-by: Anthony <anthony@zed.dev>
d9a94a5496Danilo Leal committed on 8/13/2025, 4:18:24 PM· committed by GitHubparenta7442d8