fix(api): preserve 64-bit integer schema formats (#5908)

Co-authored-by: sanmaxdev <sanmaxdev@users.noreply.github.com>

tools/openapigen/emit_jsonschema_test.go

@@ -0,0 +1,30 @@
+package main
+
+import "testing"
+
+func TestIntegerSchemaFormats(t *testing.T) {
+	tests := []struct {
+		name       string
+		goType     string
+		wantFormat string
+	}{
+		{name: "int", goType: "int"},
+		{name: "int32", goType: "int32"},
+		{name: "int64", goType: "int64", wantFormat: "int64"},
+		{name: "uint64", goType: "uint64", wantFormat: "int64"},
+	}
+
+	gen := &schemaGen{}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			schema := gen.typeSchema(identType(tt.goType))
+			if got := schema["type"]; got != "integer" {
+				t.Fatalf("type = %v, want integer", got)
+			}
+			got, _ := schema["format"].(string)
+			if got != tt.wantFormat {
+				t.Fatalf("format = %q, want %q", got, tt.wantFormat)
+			}
+		})
+	}
+}