audit(0087): cycle close — drift-clean after C24/C9 realization note; rm ephemeral spec/plan

Architect drift review of cycle 0087 (#155, the C24 blueprint-serialization-and-
loader first cut). What holds (confirmed against the diff): C17 / no-RustAst (the
format carries only type identity + name + bound params + topology; the build
closure is dropped and re-derived, no node logic in the data); invariant 9 /
domain-free engine (injected resolver, the closed match in aura-std, engine lib
deps aura-core + aura-analysis only — a compiled-in closed set, not a dynamic
registry); C9 round-trip / C23 bootstrap untouched (loader's terminal step is the
unchanged Composite::new -> bootstrap_with_params; validation deferred to the
existing gate, not bypassed).

Resolution:
- fix (ledger): C24 Status refreshed from "unbuilt" to "first cut shipped"
  with a cycle-0087 realization note; C9's round-trips-both-ways refinement
  marked realised. The ledger no longer contradicts the code.
- backlog (debt-med): the hand-written std_vocabulary match has no guard test
  that fails when a new zero-arg aura-std node lacks an arm — fails safe today
  (clean UnknownNodeType, never silent-wrong). Filed as #160.
- carry-on (scaling): construction-arg builders + sinks excluded, so no real
  harness round-trips yet; harness retirement blocks on the construction +
  project-as-crate layers — already tracked #156/#157/#159.

No architect-sweep / regression script is declared in the project facts, so the
suite is the gate: cargo test --workspace 748 passed (737 -> 748 = the 11 new
tests); clippy --all-targets -D warnings clean.

Ephemeral cycle artifacts removed (lifecycle convention): docs/specs/0087-*,
docs/plans/0087-*.

docs/design/INDEX.md

@@ -486,7 +486,8 @@ blueprint is not only *emitted* as data (`model_to_json`, the render half) but i
 itself a **serializable data value with a load path** (data → blueprint →
 `FlatGraph`), so topology is a value the World generates, stores, and reproduces —
 see C24. The Rust builder API stays the primary *human / LLM* authoring surface
-(C17); the data form is the *machine* surface the World owns.
+(C17); the data form is the *machine* surface the World owns. (Load path **realised**
+cycle 0087 / #155, `d5602ec`: `aura-engine::blueprint_from_json`.)
 
 ### C10 — Strategy output is a bias stream; signal quality is measured in R; cost is a composable downstream graph (gross R → net R); money is decoupled to the live deploy edge
 **Guarantee.** A strategy's primary, backtestable output is **not** an equity
@@ -1779,16 +1780,30 @@ thread) force the **value**. The engine already treats topology as a runtime val
 (C9 graph-as-data, C19 "cheap graph re-compilation, not a code recompile", C23 the
 flat graph as the optimisation target); C24 only adds that the value **serializes out
 of Rust and loads back in**.
-**Status (2026-06-29).** The **principle** is settled (this contract, ratified in an
-in-context design discussion — the #109 resolution). The **format itself** — the
-concrete data structure, serialization, the data → blueprint loader, and
-content-addressing for identity (C18) — is **unbuilt**, the next brainstorm /
-milestone. `model_to_json` (C9) is the one-directional half that exists.
-Sequencing-coupled to the **project-as-crate authoring layer** (`aura new` /
+**Status (2026-06-29; first cut shipped — cycle 0087 / #155, `d5602ec`).** The
+**principle** is settled (this contract, ratified in an in-context design discussion
+— the #109 resolution). The **first cut now ships**: a `Composite` blueprint
+serializes to a **canonical, versioned** data value (`format_version` envelope,
+omit-defaults JSON) and **loads back** (data → blueprint → `FlatGraph`) via
+`blueprint_to_json` / `blueprint_from_json` (`aura-engine::blueprint_serde`),
+referencing nodes by **compiled-in type identity** through an **injected resolver**
+whose concrete closed `match` over the `aura-std` vocabulary lives outside the engine
+(`aura-std::std_vocabulary`) — the engine stays domain-free, no node registry
+(invariant 9). Acceptance met: a serialized blueprint runs **bit-identical** (C1) to
+its Rust-built twin. `model_to_json` (C9) remains the render half; this closes the
+loop for the round-trippable vocabulary. **Remaining** (each its own milestone
+issue): the forward-compat *must-understand* gate (#156); the introspectable
+construction service that *emits* blueprints (#157); content-addressed topology
+identity in the manifest (#158, C18); retiring the pre-C24 hard-wired `aura-cli`
+harnesses (`HarnessKind`, `run_stage1_r`, `*_sweep_family`) once the construction +
+project-as-crate layers land (#159). **Out of the first cut's round-trippable set**
+(deliberate; fails clean as `UnknownNodeType`, never a silent wrong graph): recording
+sinks (capture an `mpsc::Sender` — runtime identity, not param-generic data, C19) and
+construction-arg builders (`LinComb` / `CostSum` / `SimBroker` / `Session` —
+structural-axis args, a C20 concern), additively addable later (#156). Still
+sequencing-coupled to the **project-as-crate authoring layer** (`aura new` /
 `Aura.toml` / `cdylib` loading, C16/C17) and the **composable-orchestration** thread
-(#109): topology-as-data is the substrate both stand on. The pre-C24 hard-wired
-harnesses (`HarnessKind`, `run_stage1_r`, the per-strategy `*_sweep_family` in
-`aura-cli`) are scaffolding retired as it lands.
+(#109): topology-as-data is the substrate both stand on.
 
 ---