Add OpenAPI specification support to the agent. Implement a new endpoint for serving OpenAPI documentation and refactor the existing handler to utilize the new specification. Add tests to ensure the correctness of the OpenAPI spec generation.

lib/openapi/spec_test.go

@@ -0,0 +1,25 @@
+package openapi
+
+import "testing"
+
+func TestSpec(t *testing.T) {
+	spec := Spec()
+	if spec["openapi"] != "3.0.3" {
+		t.Fatalf("openapi version = %v", spec["openapi"])
+	}
+	paths, ok := spec["paths"].(map[string]any)
+	if !ok || len(paths) < 12 {
+		t.Fatalf("expected at least 12 paths, got %d", len(paths))
+	}
+	if _, ok := paths["/api/v1/status"]; !ok {
+		t.Fatal("missing /api/v1/status")
+	}
+	components, ok := spec["components"].(map[string]any)
+	if !ok {
+		t.Fatal("missing components")
+	}
+	schemas, ok := components["schemas"].(map[string]any)
+	if !ok || len(schemas) < 10 {
+		t.Fatalf("expected schemas, got %d", len(schemas))
+	}
+}