Validation: Four-role docs update (#119)

validation-119-2026-06-06 Doc

validation pass

Ticket

#119 — Update docs for four-role model, tab layout, and multi-tenancy. PR #120 merged (squash).

Environment

Docs only — no runtime validation needed.

Checks

# Criterion Result
1 All docs in docs/ linked from README PASS
2 Four-role model documented in user-stories-auth.md PASS
3 ROADMAP.md removed (project management in pal-e-docs) PASS
4 App architecture and hotwire docs updated PASS

Verdict

PASS — QA-reviewed, nits fixed, Lucas approved merge.