Add phase-1 Ansible foundation and validation scaffolding

docs/infrastructure-inventory.md

@@ -25,11 +25,18 @@ This is currently the most structured host/VM inventory in the repo.
 
 These resources should match existing running containers, not redefine runtime composition strategy.
 
-### 3) Compose runtime definitions
+
+### 3) Ansible bootstrap layer
+
+`infrastructure/ansible/` provides an emerging inventory/configuration scaffold for hosts and devices.
+
+Current scope is intentionally limited to structure, variables scaffolding, and safe validation workflows.
+
+### 4) Compose runtime definitions
 
 Compose files define intended service runtime composition, networking, labels, and integration.
 
-### 4) Architecture docs
+### 5) Architecture docs
 
 `docs/architecture.md` provides a human-readable topology view based on repository configuration and observed runtime signals.
 
@@ -46,6 +53,7 @@ When adding Terraform outputs for documentation/tooling:
 
 - No full generated inventory document pipeline is present yet.
 - Some Terraform files still include generated boilerplate comments requiring ongoing cleanup.
-- Ansible/NixOS operational layers are not yet implemented in a way that provides authoritative inventory in this repo.
+- Ansible is currently a bootstrap inventory/configuration layer and is not authoritative for full operations yet.
+- NixOS operational management is not yet implemented as an Ansible authority in this repo.
 
 These limitations are expected for the current adoption stage.