fix(confidence-engine): enforce openai strict object invariants

tests/llm/provider.test.js

@@ -190,6 +190,30 @@ describe("OllamaLlmProvider chat capability detection", () => {
 });
 
 describe("OpenAI reconstruction provider experiment seam", () => {
+  function assertStrictObjectInvariant(schema, root = schema, visited = new Set()) {
+    if (!schema || typeof schema !== "object" || visited.has(schema)) return;
+    visited.add(schema);
+
+    if (schema.properties) {
+      expect(schema.additionalProperties).toBe(false);
+      expect(new Set(schema.required)).toEqual(new Set(Object.keys(schema.properties)));
+      Object.values(schema.properties).forEach((property) =>
+        assertStrictObjectInvariant(property, root, visited),
+      );
+    }
+    if (schema.items) assertStrictObjectInvariant(schema.items, root, visited);
+    for (const branch of [
+      ...(schema.anyOf ?? []),
+      ...(schema.oneOf ?? []),
+      ...(schema.allOf ?? []),
+    ]) {
+      assertStrictObjectInvariant(branch, root, visited);
+    }
+    for (const definition of Object.values(schema.$defs ?? schema.definitions ?? {})) {
+      assertStrictObjectInvariant(definition, root, visited);
+    }
+  }
+
   it("projects canonical optional fields as required but nullable", () => {
     const nativeSchema = z.toJSONSchema(reconstructionV2Schema);
     const projectedSchema = createOpenAIStrictSchema(
@@ -351,6 +375,10 @@ describe("OpenAI reconstruction provider experiment seam", () => {
       relationships: [],
       possibleFollowUpQuestions: [],
     });
+    expect(new Set(schema.required)).toEqual(new Set(Object.keys(schema.properties)));
+    expect(schema.properties).toHaveProperty("relationships");
+    expect(schema.required).toContain("relationships");
+    assertStrictObjectInvariant(schema);
   });
 
   it("recursively projects arbitrary nested object schemas as strict", () => {