1. Add onClientCreated And onConfigClient parameter

[wilinz]

1. Add onClientCreated parameter to set request interceptors for httpClient.
2. Add onConfigClient parameter to configure HttpClient, such as adding a cookie manager.

Q	A
New feature?	yes

Describe your change

1. Add onClientCreated parameter to set request interceptors for httpClient.
2. Add onConfigClient parameter to configure HttpClient, such as adding a cookie manager.

What problem is this fixing?

1. onClientCreated: Many existing Android apps typically use okhttp as their http client. Now I have implemented a forwarding server for the OpenAI API, which has the same interface as the official one. This avoids exposing the apikey in the frontend and prevents apikey leakage. Therefore, I changed the authentication method to cookie authentication. This means I need to set the cookie header for the http client in the SDK. However, the cookie may change frequently, so it cannot be simply passed as a parameter through OpenAIConfig's headers. Therefore, I need to set a request interceptor for the SDK's http client. Here is an example:

    var cookieJar =
        PersistentCookieJar(SetCookieCache(), SharedPrefsCookiePersistor(MyApplication.instance))

    val openAI = OpenAI(
        token = "",
        logging = LoggingConfig(LogLevel.All),
        host = OpenAIHost(baseUrl = "http://127.0.0.1/v1/"),
        onClientCreated = {
            it.plugin(HttpSend).intercept { request ->
                fun cookieHeader(cookies: List<Cookie>): String = buildString {
                    cookies.forEachIndexed { index, cookie ->
                        if (index > 0) append("; ")
                        append(cookie.name).append('=').append(cookie.value)
                    }
                }
                val cookie = cookieJar.loadForRequest(request.url.buildString().toHttpUrl())
                request.headers.append("Cookie", cookieHeader(cookie))
                execute(request)
            }
        },
    )

2. onConfigClient: This parameter allows you to configure the http client with additional options, such as:

val openAI = OpenAI(
    token = "",
    logging = LoggingConfig(LogLevel.All),
    host = OpenAIHost(baseUrl = "http://127.0.0.1/v1/"),
    onConfigClient = {
        install(HttpCookies)
    }
)