Fix 64-bit numeric enum values in typescript (#7135)

* Fix 64-bit default numeric enum values in typescript

If you had a default value that wasn't a valid enum value (e.g., a zero
if you used a bit_flag setting, like you get with AdvancedFeatures
in reflection.fbs), we weren't using BigInt.

* Run generate_code.py

* [DART] Handle deprecated fields & invalid enum defaults

* Update .NET test

tests/monster_test.fbs

@@ -31,6 +31,14 @@ enum Race:byte {
   Elf,
 }
 
+enum LongEnum:ulong (bit_flags) {
+  LongOne = 1,
+  LongTwo = 2,
+  // Because this is a bitflag, 40 will be out of range of a 32-bit integer,
+  // allowing us to exercise any logic special to big numbers.
+  LongBig = 40,
+}
+
 union Any { Monster, TestSimpleTableWithEnum, MyGame.Example2.Monster }
 
 union AnyUniqueAliases { M: Monster, TS: TestSimpleTableWithEnum, M2: MyGame.Example2.Monster }
@@ -125,6 +133,10 @@ table Monster {
   testrequirednestedflatbuffer:[ubyte] (id:49, nested_flatbuffer: "Monster");
   scalar_key_sorted_tables:[Stat] (id: 50);
   native_inline:Test (id: 51, native_inline);
+  // The default value of this enum will be a numeric zero, which isn't a valid
+  // enum value.
+  long_enum_non_enum_default:LongEnum (id: 52);
+  long_enum_normal_default:LongEnum = LongOne (id: 53);
 }
 
 table TypeAliases {