phase: 10, status: plan-as-execute, persona: platform-engineer, task: T-10.1..T-10.3+T-10.6

---ci---
project: acdl
phase: 10
milestone: v1.1
status: plan-as-execute
persona: platform-engineer
task: [T-10.1, T-10.2, T-10.3, T-10.6]
requirements.covered: [REQ-25]
---/ci---

Wave 1: L2 thin-composition + registry extension + adapter L2 handling.

- T-10.1: modules-ir/l2/l2-static-asset/composition.json (kind=l2, depth=1,
  one child l1-s3@1.0.0, wires passthrough).
- T-10.2: modules-ir/registry.json extended with l2-static-asset@1.0.0.
- T-10.3: modules-ir/l2/l2-static-asset/README.md (D-P10-1 doc).
- T-10.6: adapters/terraform/adapter.py - backend key now derived from
  the stack name (spike/<stack_name>/terraform.tfstate). The resources
  array handling is unchanged; a resolved L2 IR instance has the L1
  resource as resources[0], so the existing TYPE_MAP + resource emission
  handle it (the adapter is shape-driven, not kind-driven).

modules-ir/l2/l2-static-asset/README.md

@@ -0,0 +1,31 @@
+# l2-static-asset — thin-composition (S3 static asset)
+
+The v1.1 spike's L2. A thin-composition that references `l1-s3` only
+(depth 1). The contract's inputs (`bucket_name`, `region`) map 1:1
+through the wires to the L1's inputs.
+
+## Composition (the IR-typed thin-composition tree)
+
+See `composition.json`: `kind=l2`, `depth=1`, one child `l1-s3@1.0.0`,
+wires `{bucket_name → s3.inputs.bucket_name, region → s3.inputs.region}`
+(passthrough).
+
+## IR → Terraform mapping (D-P10-1)
+
+The Terraform adapter consumes the *resolved IR instance* (which has
+`kind=l2` + the L1 resource `s3` in its `resources` array). For a
+depth-1 thin-composition, the L2 root module **IS** the L1's resource —
+no separate `module "l1_s3" { source = "..." }` block. The existing
+adapter `TYPE_MAP` + resource emission handle both l1 and l2 instances
+(the resources array is the same shape). The `relationships` array is
+ignored at the Terraform level for the spike (composition ordering is
+implicit in the single resource).
+
+v1.2 may emit a real `module "l1_s3" { source = "..." }` block when L1s
+become published Terraform modules rather than inline resources.
+
+## Versioning (W3.D)
+
+`1.0.0` — interface MAJOR, behavior MINOR, lifecycle PATCH. MAJOR bumps
+require a new registry entry (immutable publication); old entries enter
+a 12-month deprecation window.

modules-ir/l2/l2-static-asset/composition.json

@@ -0,0 +1,17 @@
+{
+  "name": "l2-static-asset",
+  "version": "1.0.0",
+  "kind": "l2",
+  "depth": 1,
+  "description": "Thin-composition: a single S3 bucket for static asset hosting. References l1-s3 only (depth 1).",
+  "children": [
+    {
+      "id": "s3",
+      "module": "l1-s3@1.0.0"
+    }
+  ],
+  "wires": {
+    "bucket_name": {"target": "s3", "input": "bucket_name"},
+    "region": {"target": "s3", "input": "region"}
+  }
+}