CHANGELOG.md gains an Added section at the top of [Unreleased] that
walks the redesign decisions: PRODUCT/DESIGN docs, WinUI 3 scaffold,
MainWindow IA, ThemeManager, Settings drawer, Help/About/Onboarding,
HTML preview, migration plan. Calls out the WPF host as the still-
shipping build until WinUI 3 reaches feature parity.
README.md picks up:
- A Status section paragraph naming the in-flight redesign and the
current activation blocker, with a pointer to Phase 3 of the
migration plan
- A Build section that names both hosts so a fresh checkout doesn't
surprise contributors with the new csproj
- Documentation section now links PRODUCT.md, DESIGN.md, the migration
plan, and the interactive HTML preview
Both docs land BEFORE Phase 4 (view-model wiring) so onlookers
understand what's already done and what's queued.
