The architecture spec for the full vision — a declarative project tool
(picloud.toml + pull/plan/apply/prune) and a server-side nested-groups
hierarchy with live-resolve inheritance. Reviewed across several passes
for consistency, gaps, and contradictions; resolutions are folded in
beside the topics they settle.
This commit lands the spec only. The first slice of implementation (the
single-app reconcile foundation) follows; groups, env-scoping, and the
`enabled` toggle are later milestones called out in the doc.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>