Add support for interface generation and enums

[APshenkin]

Description

Some engineers prefer interfaces rather than classes for typescript types. So I added option in wails.json to choose between classes and interfaces. Classes are chosen as default for backward compatibility.

Also typescriptify supports providing types for enums. https://github.com/tkrajina/typescriptify-golang-structs#enums
As generation for them is sligtly different, I added EnumBind to App configuration like this

err := wails.Run(&options.App{
		Title:  "wails-app",
		Width:  1024,
		Height: 768,
		AssetServer: &assetserver.Options{
			Assets: assets,
		},
		BackgroundColour: &options.RGBA{R: 27, G: 38, B: 54, A: 1},
		Bind: []interface{}{
			app,
		},
		EnumBind: []interface{}{
			AllWeekdays,
		},
	})

This then generate proper enums in model.ts file, so types are not missing if you return something in structs

fixes #2258
And partially solve this #2104

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration using wails doctor.

• Windows
• macOS
• Linux

Test Configuration

I created some showcase here https://github.com/APshenkin/wails-open-file/tree/feature/ts-interfaces-enums

Checklist:

• I have updated website/src/pages/changelog.mdx with details of this PR
• My code follows the general coding style of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[APshenkin]

@leaanthony curios about your input for that 😊

[leaanthony]

Thanks for this! Just a small question 👍

[leaanthony]

Actually, we should have both enum + interface tests in binding/binding_test to make sure we're tracking this going forward.

[APshenkin]

@leaanthony will write the tests for this on weekends

[APshenkin]

@leaanthony added some tests

GeneratedJsEntityWithIntEnumTest,
GeneratedJsEntityWithStringEnumTest,
GeneratedJsEntityWithEnumTsName,
GeneratedJsEntityWithNestedStructInterfacesTest,
ImportedEnumTest,

As well as fixed the case, when struct contains imported enum (before it doesn't track type for it correctly)

[APshenkin]

@leaanthony anything else that I maybe need to add it this PR?

Thanks

[leaanthony]

No, just need time to review 🙏

[APshenkin]

@leaanthony @stffabi
Just kind reminder on that 🙂

I want to use enums in my project as it will be much convenient to follow contracts between frontend and backend then 🙂

I currently use replace in go.mod but this adds additional overhead for CI/CD and other devs to install everything properly 🥲

[leaanthony]

Thanks @APshenkin 🙏