Complete REUSE-WP-0003: registry CLI, docs alignment, and coverage

Align INTENT.md with delivered layout, add CapabilityRegistryConcept guide,
extend schema with promotion_history, ship reuse-surface validate/query/export
CLI, register three more helix_forge capabilities, and refresh SCOPE and gap
analysis to reflect A3 tooling and D5/A3/C4/R2 self-assessment.

INTENT.md

@@ -205,10 +205,10 @@ maturity:
 
 external_evidence:
   completeness:
-    current: C1
+    level: C1
     confidence: low
   reliability:
-    current: R0
+    level: R0
     confidence: low
 
 discovery:
@@ -239,28 +239,40 @@ evidence:
 
 ## Initial Repository Role
 
-The initial role of `reuse-surface` is to define and maintain the capability registry model, standards, schemas, examples, and reference tooling.
+The initial role of `reuse-surface` is to define and maintain the capability
+registry model, standards, schemas, examples, and reference tooling.
 
-Likely early repository contents:
+Current repository layout (authoritative for delivery):
 
 ```text
 reuse-surface/
 ├── INTENT.md
-├── README.md
-├── standards/
+├── SCOPE.md
+├── AGENTS.md
+├── specs/
+│   ├── ProductRequirementsDocument.md
+│   ├── UseCaseCatalog.md
 │   └── CapabilityMaturityStandard.md
-├── registry/
-│   ├── capabilities.yaml
-│   └── examples/
 ├── schemas/
-│   └── capability.schema.json
+│   └── capability.schema.yaml
+├── templates/
+│   └── capability-entry.template.md
+├── registry/
+│   ├── README.md
+│   ├── capabilities/
+│   └── indexes/
+│       └── capabilities.yaml
 ├── docs/
 │   ├── CapabilityRegistryConcept.md
-│   └── CapabilityAssessmentGuide.md
+│   └── IntentScopeGapAnalysis.md
 └── tools/
     └── README.md
 ```
 
+See `SCOPE.md` for what is possible now versus planned. See
+`docs/IntentScopeGapAnalysis.md` for tracked gaps between intent and delivered
+scope.
+
 ## Success Criteria
 
 `reuse-surface` is successful when it helps humans and agents: