feat(research,registry,campaign): tap vocabulary + trace_name record contract (0109 tasks 1-2)

Task 1: the tap namespace is a closed vocabulary — tap_vocabulary()
(the wrap convention's four sink names; escalation = new entry or an
authored blueprint sink, never an open node-path namespace) with
DocFault::UnknownTap in validate_campaign (index-addressed, prose
enumerating the vocabulary via the single source), SlotKind::TapKinds
on the persist_taps slot, open-slot hint naming the taps. The 0107
deferral seam test split into its two 0109 pins (unknown tap refuses
at validate; a valid tap passes validate and hits the member-data
seam) — the deferral eprintln itself survives until task 3.

Task 2: CampaignRunRecord.trace_name lands serde-default sparse; the
claim contract holds across the seam — execute stamps the sentinel iff
persist_taps is non-empty, append_campaign_run composes
Some("{campaign8}-{run}") onto the stored line (safe prefix take at
the registry seam), execute mirrors the same derivation onto the
returned copy; None stays None; the hand-seeded byte-identity dump pin
survives (absent -> skipped).

Gates: workspace 1037/0, clippy -D warnings clean.

refs #201

crates/aura-cli/src/research_docs.rs

@@ -8,8 +8,8 @@ use std::path::PathBuf;
 use aura_research::{
     campaign_to_json, campaign_vocabulary, describe_block, open_slots_campaign,
     open_slots_process, parse_campaign, parse_process, process_to_json, process_vocabulary,
-    slot_kind_label, validate_campaign, validate_process, CampaignDoc, DocError, DocFault,
-    DocKind, ProcessDoc, StageBlock,
+    slot_kind_label, tap_vocabulary, validate_campaign, validate_process, CampaignDoc, DocError,
+    DocFault, DocKind, ProcessDoc, StageBlock,
 };
 use aura_registry::RefFault;
 
@@ -147,6 +147,10 @@ pub(crate) fn doc_fault_prose(f: &DocFault) -> String {
             format!("strategies[{strategy}].axes.{axis}: an axis is a non-empty finite set")
         }
         DocFault::UnknownEmitKind(kind) => format!("presentation.emit: unknown kind \"{kind}\""),
+        DocFault::UnknownTap { index, tap } => format!(
+            "presentation.persist_taps[{index}]: unknown tap \"{tap}\" (taps: {})",
+            tap_vocabulary().join(" | ")
+        ),
         DocFault::ProcessRefMustBeContentId => {
             "process.ref: a process is referenced by content id in this version".into()
         }
@@ -593,4 +597,20 @@ mod tests {
         assert_eq!(prose, "pipeline[2]: walk_forward step_ms must be > 0");
         assert!(!prose.contains("ZeroWalkForwardLength"), "Debug leak: {prose}");
     }
+
+    #[test]
+    /// #201 decision 1 (spec 0109): the unknown-tap refusal is path-addressed
+    /// (`presentation.persist_taps[i]`) and enumerates the closed vocabulary
+    /// inline — four names are small enough to print, so no introspection
+    /// pointer is needed (contrast the 17-name metric roster, which points at
+    /// `aura process introspect --metrics` instead).
+    fn unknown_tap_prose_is_path_addressed_and_enumerates_the_vocabulary() {
+        let prose = doc_fault_prose(&DocFault::UnknownTap { index: 0, tap: "bias".into() });
+        assert_eq!(
+            prose,
+            "presentation.persist_taps[0]: unknown tap \"bias\" \
+             (taps: equity | exposure | r_equity | net_r_equity)"
+        );
+        assert!(!prose.contains("UnknownTap"), "Debug leak: {prose}");
+    }
 }