docs: mark multi-value (List) attribute feature complete; document DataType.List + ElementDataType in Component-Commons

MV-15 integration checkpoint: full solution builds 0/0; feature-targeted tests
green across Commons, TemplateEngine, SiteRuntime, DataConnectionLayer,
Communication, Transport, ManagementService, CLI, CentralUI (255 tests).

docs/plans/2026-06-16-multivalue-attribute-design.md

@@ -1,7 +1,7 @@
 # Structured Multi-Value Attribute — Design
 
 **Date:** 2026-06-16
-**Status:** Approved (brainstorming) — ready for implementation plan
+**Status:** Implemented (MV-1 … MV-15, branch `feature/multivalue-attribute`) — full solution builds clean; feature-targeted tests green across Commons, TemplateEngine, SiteRuntime, DataConnectionLayer, Communication, Transport, ManagementService, CLI, and CentralUI.
 **Branch:** `feature/multivalue-attribute`
 
 ## Problem

docs/plans/2026-06-16-multivalue-attribute.md.tasks.json

@@ -2,22 +2,23 @@
   "planPath": "docs/plans/2026-06-16-multivalue-attribute.md",
   "designDoc": "docs/plans/2026-06-16-multivalue-attribute-design.md",
   "branch": "feature/multivalue-attribute",
+  "status": "complete",
   "tasks": [
-    {"id": 77, "ref": "MV-1", "subject": "Type model — DataType.List + ElementDataType companion", "class": "standard", "status": "pending"},
+    {"id": 77, "ref": "MV-1", "subject": "Type model — DataType.List + ElementDataType companion", "class": "standard", "status": "completed", "commits": ["70fa0e7"]},
-    {"id": 78, "ref": "MV-2", "subject": "AttributeValueCodec + tests", "class": "standard", "status": "pending", "blockedBy": [77]},
+    {"id": 78, "ref": "MV-2", "subject": "AttributeValueCodec + tests", "class": "standard", "status": "completed", "commits": ["8bd8079", "492b41f"]},
-    {"id": 79, "ref": "MV-3", "subject": "EF mapping + idempotent migration", "class": "high-risk", "status": "pending", "blockedBy": [77]},
+    {"id": 79, "ref": "MV-3", "subject": "EF mapping + idempotent migration", "class": "high-risk", "status": "completed", "commits": ["4a4b3d6"]},
-    {"id": 80, "ref": "MV-4", "subject": "Flatten carries ElementDataType", "class": "small", "status": "pending", "blockedBy": [77]},
+    {"id": 80, "ref": "MV-4", "subject": "Flatten carries ElementDataType", "class": "small", "status": "completed", "commits": ["02aff24", "492b41f"]},
-    {"id": 81, "ref": "MV-5", "subject": "Semantic validation for List attributes", "class": "standard", "status": "pending", "blockedBy": [77, 78]},
+    {"id": 81, "ref": "MV-5", "subject": "Semantic validation for List attributes", "class": "standard", "status": "completed", "commits": ["872ce2b", "6ef6bab"]},
-    {"id": 82, "ref": "MV-6", "subject": "Script-accessor encode boundary", "class": "small", "status": "pending", "blockedBy": [78]},
+    {"id": 82, "ref": "MV-6", "subject": "Script-accessor encode boundary", "class": "small", "status": "completed", "commits": ["a1d464b"]},
-    {"id": 83, "ref": "MV-7", "subject": "InstanceActor decode (load + set + override)", "class": "high-risk", "status": "pending", "blockedBy": [77, 78, 80, 82]},
+    {"id": 83, "ref": "MV-7", "subject": "InstanceActor decode (load + set + override)", "class": "high-risk", "status": "completed", "commits": ["7f97780", "ad6bfc8"]},
-    {"id": 84, "ref": "MV-8", "subject": "DCL OPC UA array read coercion", "class": "standard", "status": "pending", "blockedBy": [77, 78]},
+    {"id": 84, "ref": "MV-8", "subject": "DCL OPC UA array read coercion", "class": "standard", "status": "completed", "commits": ["4765706", "96e817a"]},
-    {"id": 85, "ref": "MV-9", "subject": "StreamRelayActor canonical-JSON encode", "class": "small", "status": "pending", "blockedBy": [78]},
+    {"id": 85, "ref": "MV-9", "subject": "StreamRelayActor canonical-JSON encode", "class": "small", "status": "completed", "commits": ["ba414cb"]},
-    {"id": 86, "ref": "MV-10", "subject": "ManagementActor add/update attribute handlers", "class": "standard", "status": "pending", "blockedBy": [77, 78, 81]},
+    {"id": 86, "ref": "MV-10", "subject": "ManagementActor add/update attribute handlers", "class": "standard", "status": "completed", "commits": ["1525670", "0164f8a"]},
-    {"id": 87, "ref": "MV-11", "subject": "CLI --element-type + JSON --value", "class": "standard", "status": "pending", "blockedBy": [86]},
+    {"id": 87, "ref": "MV-11", "subject": "CLI --element-type + JSON --value", "class": "standard", "status": "completed", "commits": ["85db457", "100540b"]},
-    {"id": 88, "ref": "MV-12", "subject": "Transport DTO + importer field", "class": "small", "status": "pending", "blockedBy": [77]},
+    {"id": 88, "ref": "MV-12", "subject": "Transport DTO + importer field", "class": "small", "status": "completed", "commits": ["e7e34b2", "492b41f"]},
-    {"id": 89, "ref": "MV-13", "subject": "Central UI — TemplateEdit list editor", "class": "standard", "status": "pending", "blockedBy": [86]},
+    {"id": 89, "ref": "MV-13", "subject": "Central UI — TemplateEdit list editor", "class": "standard", "status": "completed", "commits": ["ba7331e", "100540b"]},
-    {"id": 90, "ref": "MV-14", "subject": "Central UI — InstanceConfigure override list editor", "class": "standard", "status": "pending", "blockedBy": [86]},
+    {"id": 90, "ref": "MV-14", "subject": "Central UI — InstanceConfigure override list editor", "class": "standard", "status": "completed", "commits": ["ae2e1ef", "ca9ee5e"]},
-    {"id": 91, "ref": "MV-15", "subject": "Integration verification + docs/README sync", "class": "standard", "status": "pending", "blockedBy": [77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90]}
+    {"id": 91, "ref": "MV-15", "subject": "Integration verification + docs/README sync", "class": "standard", "status": "completed"}
   ],
   "lastUpdated": "2026-06-16"
 }

docs/requirements/Component-Commons.md

@@ -26,7 +26,7 @@ Referenced by all component libraries and the Host.
 
 Commons must define shared primitive and utility types used across multiple components, including but not limited to:
 
-- **`DataType` enum**: Enumerates the data types supported by the system (e.g., Boolean, Int32, Float, Double, String, DateTime, Binary).
+- **`DataType` enum**: Enumerates the data types supported by the system: Boolean, Int32, Float, Double, String, DateTime, Binary, and **List** (a homogeneous multi-value attribute). A `List` attribute carries a companion `ElementDataType` (one of the scalar types — String, Int32, Float, Double, Boolean, DateTime; not Binary, not nested List) on `TemplateAttribute` / `InstanceAttributeOverride` and the flattened `ResolvedAttribute`. List values are stored and transmitted as a canonical JSON array via the `AttributeValueCodec` helper (scalars keep their historical invariant-culture string form); the `ElementDataType` is fixed by the defining level and cannot be changed on a derived template or instance override.
 - **`RetryPolicy`**: A record or immutable class describing retry behavior (max retries, fixed delay between retries).
 - **`Result<T>`**: A discriminated result type that represents either a success value or an error, enabling consistent error handling across component boundaries without exceptions.
 - **`InstanceState` enum**: Enabled, Disabled.