homeplanr v0.8.0

M10 (0.8.0): release prep — version 0.8.0, CHANGELOG, RUNBOOK, roadmap

- Version 0.8.0 in package.json / tauri.conf.json / Cargo.toml+lock.
- CHANGELOG: room move/rotate/snap, per-side finishes + 4 new, 17 floor
  materials + grouped picker, room types + plan statistics, schema v5.
- RUNBOOK: 0.8.0 state paragraph; new invariants (room rig tear/weld
  rules, roomPivot sharing, spec-fallback lookups for open registries,
  roomLabelLines twins, setRoomType seeding rule); test count.
- ROADMAP: 0.8.0 implemented (awaiting user checklist → tag + publish);
  schema-batching status (v5 = finish split only; 0.9.0 assets → v6);
  v0.9.0.md bump reference fixed; v0.8.0.md gains the shipped-decisions
  record (door ownership user-confirmed, Ctrl override, arm rule,
  accepted cosmetic transients).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>