refactor(core): improve HTTP API, closes #1098

[lucasfernog]

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• Bugfix
• Feature
• New Binding Issue #___
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• Yes. Issue #___
• No

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[lucasfernog]

@nklayman I'd love to hear your inputs on the API interface (file http.ts)

[nklayman]

I think the createClient/dropClient adds some unnecessary complexity and could scare people into just using the webview fetch. Why is that necessary? If that is required, I think we should at least provide a request function that automatically creates and then drops the client.

[lucasfernog]

I think the createClient/dropClient adds some unnecessary complexity and could scare people into just using the webview fetch. Why is that necessary? If that is required, I think we should at least provide a request function that automatically creates and then drops the client.

The Client adds some optimizations but yeah we should add a global default client.