audit: #331 cycle close — every authored intake gates the root name, cli_fixed_cost re-pinned

Architect drift review (drift_found) resolved fix-path on all three
items. [high] The sweep/walkforward/mc family builders and
validate_and_register_axes read authored envelope files and
put_blueprint'd them ungated — falsifying the C29 exemption's premise
that the store is populated through gated intakes; all four sites now
gate the root name before the family/axis build (placing the gate
after the build produced a misleading unknown-axis error instead of
the gate refusal — RED-verified), with an e2e pin on the synthetic
sweep route. The decision was gate-the-routes, not weaken-the-prose:
the exemption's premise is the invariant, not a wording choice.
[medium] C24 now states the gate rule as the class it is (the op
intake plus every CLI intake reading an authored envelope from a
file; store read-back exempt, C29). [low] C23 reconciles
names-as-debug-symbols with the render name's one operational role
(trace-directory key — never compilation, identity, or execution
semantics).

Ratify: aura-bench cli_fixed_cost baseline re-pinned
(run_line_fnv 6bb0d796f760d140 -> 9bdbc3acf7b2926a). The moved metric
was caused by the #328 tidy (4474814), which switched single-run
manifest defaults from wrapped to raw axis names after that cycle's
bench rerun had already passed; bbac29d and this cycle's HEAD produce
fingerprint-identical record lines (verified with both binaries on
one scratch project), so this cycle only inherits the stale pin. All
five surfaces fingerprint OK after the re-pin.

refs #331, #328

docs/design/contracts/c23-graph-compilation.md

@@ -9,7 +9,12 @@ entirely (there is no composite in the flat graph). The blueprint's field /
 input-role *names* are **non-load-bearing** — the wiring resolves by index, and names
 survive at most as **informative debug symbols** (exactly as `FieldSpec.name` already
 is, C8), kept for tracing / rendering (C9 graph-as-data) but carrying no run
-semantics. The flat graph is then the target of **behaviour-preserving optimisation**
+semantics. (Reconciling with the root composite's own render name, #331: that
+claim stands unweakened — the name never influences compilation, identity, or
+execution semantics — but at *run* time, outside compilation, it keys the trace
+directory (`traces/<name>/`); that operational role, not any load-bearing
+weight inside the flat graph, is exactly why the authored-blueprint intakes
+shape-gate it.) The flat graph is then the target of **behaviour-preserving optimisation**
 — any transform that leaves every observable sink trace bit-identical (C1 is the
 correctness invariant) — on two levels:
 

docs/design/contracts/c24-blueprint-data.md

@@ -202,9 +202,14 @@ replayed in order; nodes are referenced **by identifier**, ports as dotted
   (#331), script-level and at-most-once (a second refuses); omitted, the
   built composite keeps the CLI's own seed default (`"graph"`). Gated by a
   shared shape check (non-empty, single path segment, no `/`, `\`, `.` or
-  `..`) applied at both data-borne birth routes — this op intake and the
-  blueprint-envelope root name — since store read-back (reproduce, `use`
-  resolution) stays ungated per C29.
+  `..`) applied at this op intake **plus every CLI intake that reads an
+  authored blueprint envelope from a file** — `register`, `introspect
+  --content-id <FILE>`, the bare graph-file viewer, `run`, `introspect
+  --params <FILE>`, and each of `sweep`/`walkforward`/`mc`/`generalize`'s
+  file-reading entry points (synthetic and `--real` alike) — one class of
+  intake, one gate. Store read-back (`reproduce`, `use` resolution,
+  `introspect`/`--params` by content id) stays deliberately ungated — C29: a
+  registered artifact is never retroactively invalidated.
 - `source` — `{"op":"source","role":<str>,"kind":<ScalarKind>}` — declare a root
   source role producing a base column of `kind`.
 - `input` — `{"op":"input","role":<str>}` — declare a root input role (kind inferred