docs: improve docs

docs/content/1.get-started/3.client/2.links/1.httpLink.md

@@ -0,0 +1,58 @@
+---
+title: HTTP Link
+description: httpLink is a terminating link that sends a tRPC operation to a tRPC procedure over HTTP.
+---
+
+# HTTP Link
+
+`httpLink` is a [terminating link](https://trpc.io/docs/links#the-terminating-link) that sends a tRPC operation to a tRPC procedure over HTTP.
+
+`httpLink` supports both POST and GET requests.
+
+::alert{type="info"}
+`httpLink` imported from `trpc-nuxt/client` is a convenience wrapper around the original `httpLink` that replaces regular `fetch` with a [`$fetch`](https://nuxt.com/docs/api/utils/dollarfetch) from Nuxt. It also sets the default headers using [`useRequestHeaders`](https://nuxt.com/docs/api/composables/use-request-headers#userequestheaders).
+::
+
+## Usage
+
+You can import and add the `httpLink` to the `links` array as such:
+
+```ts
+import { createTRPCNuxtClient, httpLink } from 'trpc-nuxt/client'
+import type { AppRouter } from '~/server/trpc/routers'
+
+const client = createTRPCNuxtClient<AppRouter>({
+  links: [
+    httpLink({
+      url: '/api/trpc',
+    }),
+  ],
+})
+```
+
+## `httpLink` Options
+
+The `httpLink` function takes an options object that has the `HTTPLinkOptions` shape.
+
+```ts
+export interface HTTPLinkOptions {
+  url: string;
+  /**
+   * Select headers to pass to `useRequestHeaders`.
+   */
+  pickHeaders?: string[];
+  /**
+   * Add ponyfill for fetch.
+   */
+  fetch?: typeof fetch;
+  /**
+   * Add ponyfill for AbortController
+   */
+  AbortController?: typeof AbortController | null;
+  /**
+   * Headers to be set on outgoing requests or a callback that of said headers
+   * @link http://trpc.io/docs/v10/header
+   */
+  headers?: HTTPHeaders | (() => HTTPHeaders | Promise<HTTPHeaders>);
+}
+```