refactor(confidence-engine): extract focused deconstruction seam

lib/graph/focused-investigation.js

@@ -189,4 +189,55 @@ export function validateFocusedDeconstructSchema(result) {
   return errors;
 }
 
+/**
+ * Compose a focused answer deconstruction invocation.
+ *
+ * Accepts explicit provider and modelName — does NOT call getProvider or getProviderModelName.
+ * Calls buildFocusedDeconstructPrompt internally to produce the prompt.
+ * Calls provider.generateReconstruction exactly once.
+ * Validates result with validateFocusedDeconstructSchema.
+ * Returns validated semantic payload on success, or { validation: false, errors } on schema failure.
+ */
+export function focusedDeconstruct({
+  provider,
+  modelName,
+  targetNodeId,
+  targetLabel,
+  targetDescription,
+  centralStatement,
+  question,
+  answer,
+}) {
+  const prompt = buildFocusedDeconstructPrompt({
+    targetLabel,
+    targetDescription,
+    centralStatement,
+    question,
+    answer,
+  });
+
+  const wrapper = provider.generateReconstruction(
+    prompt,
+    modelName,
+    focusedDeconstructJsonSchema,
+  );
+
+  const deconstruction = wrapper.response;
+
+  const validationErrors = validateFocusedDeconstructSchema(deconstruction);
+  if (validationErrors.length > 0) {
+    return { success: false, validation: false, errors: validationErrors };
+  }
+
+  return {
+    success: true,
+    targetNodeId,
+    observations: deconstruction.observations,
+    uncertainties: deconstruction.uncertainties,
+    assumptions: deconstruction.assumptions,
+    relationships: deconstruction.relationships,
+    possibleFollowUpQuestions: deconstruction.possibleFollowUpQuestions,
+  };
+}
+
 export { FOCUSED_ANSWER_SCHEMA_FIELDS, FORBIDDEN_GRAPH_MUTATION_FIELDS };