Typescript Extension: Provide public API-surface for extension authors

[mrcrowl]

As an extension author, I'd like access to the same typescript client that is contained within the built-in typescript extension.

Some examples of useful APIs below:

/// [typescriptMain.ts]

export function activate(context: ExtensionContext): DependentExtensionAPI {
    ...

    return {
        // --> typescriptServiceClient.execute
        clientExecute(command: string, args: any, expectsResultOrToken?: boolean | CancellationToken): Promise<any> 

        // --> taskProvider.getTsConfigForActiveFile
        getTsConfigForActiveFile(): Promise<string>
    }
}

export interface DependentExtensionAPI 
{
    clientExecute(command: 'configure', args: Proto.ConfigureRequestArguments, token?: CancellationToken): Promise<Proto.ConfigureResponse>;
    clientExecute(command: 'open', args: Proto.OpenRequestArgs, expectedResult: boolean, token?: CancellationToken): Promise<any>;
    clientExecute(command: 'close', args: Proto.FileRequestArgs, expectedResult: boolean, token?: CancellationToken): Promise<any>;
    clientExecute(command: 'change', args: Proto.ChangeRequestArgs, expectedResult: boolean, token?: CancellationToken): Promise<any>;
    clientExecute(command: 'geterr', args: Proto.GeterrRequestArgs, expectedResult: boolean, token?: CancellationToken): Promise<any>;
    clientExecute(command: 'quickinfo', args: Proto.FileLocationRequestArgs, token?: CancellationToken): Promise<Proto.QuickInfoResponse>;
    clientExecute(command: 'completions', args: Proto.CompletionsRequestArgs, token?: CancellationToken): Promise<Proto.CompletionsResponse>;
    ...
    getTsConfigForActiveFile(): Promise<string>;
}

@dbaeumer

[mjbvz]

Closing as out of scope. If you still think you need some additional data or functionality from TS, please explain what you are trying to achieve and we can work back from there