§7 M3 (part 2): planning a change to a GROUP node now reports the descendant
apps owned by OTHER projects that the change fans out to — the cross-repo
signal an operator needs before touching shared config.
- OwnershipPreview gains `blast_radius: Vec<ProjectImpact>`; `group_blast_radius`
walks the group's subtree (recursive CTE) and groups descendant apps by their
nearest-claimed-ancestor project, excluding the planning project. Ancestor
resolution is memoized per group (one walk per distinct descendant group, not
per app).
- `pic plan` renders `blast_radius` rows (mode-agnostic).
- the apply_ownership journey gains a plan-preview case pinning both the
ownership annotation (claim / conflict) and the blast radius (two other
projects' apps surfaced) end to end.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>