[Typescript] Enum types

[ksvirkou-hubspot]

#14569

Added enumType generator argument:

• stringUnion - "available" | "pending" | "sold"
• enum - { Available = 'available', Pending = 'pending', Sold = 'sold' }

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[ksvirkou-hubspot]

@bodograumann
@TiFu @taxpon @sebastianhaas @kenisteward @Vrolijkx @macjohnny @topce @akehir @petejohansonxo @amakhrov @davidgamero @mkusaka

[bodograumann]

Nice work.

I would have given a bit more details in the help:

|enumType|Specify the enum type which should be used in the client code.|<dl><dt>**stringUnion**</dt><dd>Union of literal string types</dd><dt>**enum**</dt><dd>Typescript's [string enums](https://www.typescriptlang.org/docs/handbook/enums.html#string-enums)</dd></dl>|stringUnion|

But I realized, that doing this in the java-generated cli help as well would be more difficult, so I think it's fine as-is.

[ksvirkou-hubspot]

Nice work.

I would have given a bit more details in the help:

|enumType|Specify the enum type which should be used in the client code.|<dl><dt>**stringUnion**</dt><dd>Union of literal string types</dd><dt>**enum**</dt><dd>Typescript's [string enums](https://www.typescriptlang.org/docs/handbook/enums.html#string-enums)</dd></dl>|stringUnion|

But I realized, that doing this in the java-generated cli help as well would be more difficult, so I think it's fine as-is.

Done

[ksvirkou-hubspot]

@bodograumann
Could you merge it, please?

[bodograumann]

Sorry, I don't have any elevated access here 😉 @ksvirkou-hubspot. Maybe @TiFu or @wing328 can.

[macjohnny]

please default to enum for backwards compatibility

[bodograumann]

The rational here was that a breaking change was (kind of accidentally) introduced in #14663.
So this pr fixes that.
Personally I would be ok with either solution.

[macjohnny]

ah i see. well i guess i would still lean towards making enum the default, since 7.0.0 was released a while ago

[ksvirkou-hubspot]

I've done it
Could you check it, please?