Encode accepts non-conformant JS Values for OrToken

[Innkst]

Description
In the spirit of enforcing type checking on the JS side that is equivalent to that on the Micheline side, OrToken.Encode(val) should only accept an object with a single key, one that corresponds to a Micheline Left-Right position, and one whose type is consistent with the Micheline type found in that Left-Right position of the root OrToken.

The current OrToken.Encode(val) accepts objects with multiple keys. It traverses the root OrToken looking for non-or Token with a matching key. Processing terminates with the first one found. This allows a developer to erroneously conclude that they have successfully encoded a JS object with multiple keys, as an equivalent JSON encoded Micheline value. In the spirit of tight type checking any attempt to OrToken.Encode a val with more than one key should fail.

Steps To Reproduce
Consider the following:

Or1
   Or2
      int
      string
      %A
   Bool

Or1.Execute(val) maps conformant JSON-encoded Micheline values to a flat object with a single key.

Left (Left 5) maps to {“0”: 5}
Left (Right “foo”) maps to {“1”: “foo”}
Right True maps to {“2”: true}

However, Or1.Encode( {“0”: 5, “1”: “foo”, “2”: true}) returns a JSON-encoded value for:
Left (Left 5). The other key-value pairs of are simply ignored. A correct result would be for the Encode to raise an invalid-type error.

Expected behavior
Add logic to OrToken.Encode(val) to ensure that any attempt to encode a val with more than one key fails.

Additional context
Refer to AS-IS OrToken document