feat(engine,cli): run manifests stamp untouched bound defaults (closes #249)

RunManifest gains defaults: Vec<(String, Scalar)> — the wrap-prefixed
bound_param_space() of the signal, read after axis reopening, so a
bound param an axis overrode has already left the space and flows
through params instead (disjoint by construction; verified end to end:
a sweep member's overridden fast.length sits in params while
slow.length/bias.scale sit in defaults). params keeps its "what varied"
semantics and stays the reproduce input. One-directional serde
widening (#[serde(default)]) per the selection/instrument/topology_hash
idiom — old records deserialize with an empty defaults; unlike the
Option fields it always serializes, mirroring params. ~20
struct-literal sites across five crates gained the field
(compile-mandated breadth, no behaviour change at those sites).

The C14 ledger records the underlying decision (2026-07-13): generated
outcome records spend redundancy on direct readability (single writer,
cannot drift); authored intent artifacts admit none (every redundancy
is a drift site) — so the fix lands in the manifest, never the
blueprint.

Verification: RED test run_manifest_stamps_untouched_bound_defaults
green; cargo build --workspace; cargo test --workspace green; clippy
-D warnings on the touched crates; binary-level sweep exclusivity
check.

docs/design/INDEX.md

@@ -1211,6 +1211,18 @@ every hand-rolled usage line reads `Usage: aura <verb> …` (#179, cycle 0101);
 refusal diagnostics stay unprefixed (diagnostics are not usage lines). The
 machine-first help surface (JSON/manifest help, stdin op-scripts) stays on the
 #157/C21 track, not this cycle (settled as human/GNU convention compliance).
+**Amendment (2026-07-13, #249 — two artifact classes, two redundancy budgets).**
+The data layer the programmatic face emits is a public interface read raw (by
+humans and LLMs), and its records split into two classes with opposite
+redundancy budgets: **generated outcome records** (manifests, metrics, family
+reports) have a single writer at run time — redundancy there cannot drift and
+is deliberately spent on direct readability; **authored intent artifacts**
+(blueprints, op-scripts, campaign documents) are author-maintained — every
+redundancy is a drift site and stays out. Consequence shipped with #249: a run
+manifest stamps the untouched bound defaults (`defaults`, one-directionally
+widened beside `params`, which keeps its "what varied" reproduce semantics) so
+a raw reader of a fully-bound run no longer sees a misleading `"params": []`;
+the blueprint itself carries no such duplication.
 
 ### C15 — Resampling-as-node; sessions/calendars
 **Guarantee.** A resampler is a node (finer stream → coarser bar stream),