fix: architecture review - address 5 critical issues, 6 warnings, 3 suggestions

Critical fixes:
- C1: Create standalone ADR-006 file (edge type consistency),
  extract from open-questions.md inline content
- C2: Convert CallResult from plain interface to TypeBox schema,
  aligning with 'TypeBox as single source of truth' constraint
- C3: Add fromJSON() cycle detection specification - enforce
  ADR-002 DAG invariant even on deserialized input
- C4: Rewrite consumer-integration.md Phase 4 to use ADR-005
  event-append pattern instead of direct signal mutation
- C5: Fix operator precedence bug in consumer-integration.md
  (missing parentheses around OR condition)

Warnings addressed:
- W1: Fix immutability claim - operation graph is 'conventionally
  immutable', not prevented by API
- W2: Add EventLogProjection to reactive exports map
- W3: Add CallResult/CallResultSchema to schema exports map
- W4: Fix reactive-execution.md Level 1 error handling to use
  event-append pattern instead of direct signal mutation
- W5: Remove duplicate dataFlow inference description in schema.md
- W6: Clarify ADR-006 project context (flowgraph vs taskgraph)

Suggestions implemented:
- S1: Add 'reviewed' document lifecycle status between draft/stable,
  update all docs to reviewed status
- S2: Add carve-out note for analysis result types in schema.md
  constraints (they are ephemeral, not serialized)
- S3: Add isComplete() and getAggregateStatus() convenience methods
  to WorkflowReactiveRoot specification

docs/architecture/consumer-integration.md

@@ -1,5 +1,5 @@
 ---
-status: draft
+status: reviewed
 last_updated: 2026-05-19
 ---
 
@@ -152,22 +152,50 @@ const reactiveHost = new ReactiveHostConfig(registry, workflowRoot);
 const reactiveRoot = createRoot(reactiveHost, {});
 reactiveRoot.render(template);
 
-// 4. Subscribe to status changes and effect-driven execution
+// 4. Drive execution via the event log (ADR-005 pattern)
+// The hub coordinator appends call protocol events; the projections derive state.
 for (const [nodeId, node] of workflowRoot.nodes) {
   // Start the call when preconditions are met
   effect(() => {
-    if (node.preconditions.value && node.status.value === "idle" || node.status.value === "waiting") {
-      node.status.value = "running";
-      // getInput resolves the node's input from predecessor outputs and static config
-      // For Operation nodes, input comes from the template props or aggregated predecessor results
-      const input = resolveInput(nodeId, workflowRoot);
-      registry.execute(node.operationId, input, { parentRequestId: parentCallId })
-        .then(result => { node.status.value = "completed"; node.output.value = result; })
-        .catch(error => { node.status.value = "failed"; });
+    if (node.preconditions.value && (node.status.value === "idle" || node.status.value === "waiting")) {
+      // All preconditions satisfied — start the call by appending to the event log
+      const operationId = dag.getNodeAttributes(nodeId).name;
+      const requestId = crypto.randomUUID();
+      workflowRoot.nodeKeyToRequestId.set(nodeId, requestId);
+      
+      // Append call.requested event — the status projection derives "running" from this
+      workflowRoot.append({
+        type: "call.requested",
+        requestId,
+        operationId,
+        input: getInput(nodeId, workflowRoot),
+        timestamp: new Date().toISOString(),
+      });
+      
+      // Start the actual call — when it completes, append the result event
+      registry.execute(operationId, getInput(nodeId, workflowRoot), { parentRequestId })
+        .then(result => {
+          // Append call.responded event — the status projection derives "completed" from this
+          workflowRoot.append({
+            type: "call.responded",
+            requestId,
+            output: result,
+            timestamp: new Date().toISOString(),
+          });
+        })
+        .catch(error => {
+          // Append call.error event — the status projection derives "failed" from this
+          workflowRoot.append({
+            type: "call.error",
+            requestId,
+            error: { code: error.code, message: error.message },
+            timestamp: new Date().toISOString(),
+          });
+        });
     }
   });
   
-  // Track failures
+  // Track failures for logging
   effect(() => {
     if (node.status.value === "failed") {
       console.error(`Node ${nodeId} failed`);