spec: 0106 fix — axis declares its kind once, values are bare JSON

User veto (2026-07-03) of the per-cell tagged Scalar draft: the kind is a
property of the parameter, not of each value. An axis is now
{"kind": "I64", "values": [8, 12, 16]} — mixed-kind axes are
unrepresentable, canonical form normalizes value spelling, and the
referential kind check is one comparison per axis. Op-script binds keep
their tagged form (single-value slots). Decision log: #189.

refs #189

docs/specs/0106-research-artifact-vocabularies.md

@@ -126,8 +126,8 @@ resolution comment):
   },
   "strategies": [
     { "ref": { "content_id": "9f3a…" },
-      "axes": { "fast": [{"I64": 8}, {"I64": 12}, {"I64": 16}],
-                "slow": [{"I64": 21}, {"I64": 34}] } }
+      "axes": { "fast": { "kind": "I64", "values": [8, 12, 16] },
+                "slow": { "kind": "I64", "values": [21, 34] } } }
   ],
   "process": { "ref": { "content_id": "4e2d…" } },
   "seed": 1,
@@ -213,13 +213,21 @@ pub struct CampaignDoc {
 
 #[derive(Serialize, Deserialize, ...)]
 pub enum DocRef { ContentId(String), IdentityId(String) }  // one-of, typed slots
-pub struct StrategyEntry { pub r#ref: DocRef, pub axes: BTreeMap<String, Vec<Scalar>> }
+pub struct StrategyEntry { pub r#ref: DocRef, pub axes: BTreeMap<String, Axis> }
+pub struct Axis { pub kind: ScalarKind, pub values: Vec<Scalar> }
+// custom serde: `{"kind": "I64", "values": [8, 12, 16]}` — values are bare
+// JSON, parsed AS the declared kind
 pub enum EmitKind { FamilyTable, SelectionReport }         // closed v1 set
 ```
 
-Axis cells are typed `aura_core::Scalar` values — the same typed-cell
-pattern the op-script binds use (`OpDoc::Add { bind: BTreeMap<String,
-Scalar> }`, crates/aura-cli/src/graph_construct.rs:37).
+An axis declares its `ScalarKind` **once** — the kind is a property of the
+parameter, not of each value (user veto, 2026-07-03, of a per-cell tagged
+draft), so a mixed-kind axis is unrepresentable rather than merely refused.
+The op-script binds keep their per-cell tagged `Scalar` form
+(`OpDoc::Add { bind: BTreeMap<String, Scalar> }`,
+crates/aura-cli/src/graph_construct.rs:37): a bind slot holds exactly one
+value, so there the tag is the only kind carrier; an axis is a homogeneous
+list, so the kind belongs to the axis.
 
 ### Validation, canonical form, introspection (secondary shapes)
 
@@ -254,8 +262,10 @@ pub fn put_campaign(…) / get_campaign(…);              // same pattern as pu
 pub fn validate_campaign_refs(doc: &CampaignDoc, roots: &StoreRoots)
     -> Vec<RefFault>;
 // RefFault: ProcessNotFound(id), StrategyNotFound(id), IdentityAmbiguityEmpty(id),
-// AxisNotInParamSpace{strategy_ref, axis} — axes ⊆ the referenced blueprint's
-// param_space (blueprint loaded from the store via blueprint_from_json).
+// AxisNotInParamSpace{strategy_ref, axis}, AxisKindMismatch{strategy_ref, axis}
+// — axes ⊆ the referenced blueprint's param_space, and each axis's declared
+// kind must equal the param's ScalarKind (one check per axis; blueprint
+// loaded from the store via blueprint_from_json).
 ```
 
 Intrinsic P1 constraints enforced (the ratified ceiling made structural):