Wrap types in namespace for --ts-flat-files and --gen-all (#7451)

* Wrap types in namespace for --ts-flat-files and --gen-all

* Fixes for escaping object types

* Added to generate_code

tests/flatc/bar/baz/baz_with_ns.fbs

@@ -0,0 +1,8 @@
+namespace baz;
+
+enum Baz : short {
+  None = 0,
+  Red,
+  Green,
+  Blue,
+}