refactor!: remove @dfinity/use-auth-client source code (#1264)

# Description

Follow-up of #1125.

The package has already been deprecated on NPM a while ago.

Author: ilbertt

packages/use-auth-client/.gitignore

@@ -1,73 +1,6 @@
 # @dfinity/use-auth-client
 
-> **⚠️ DEPRECATED**: This package is deprecated since v3.2.3. Please use one of the following alternatives:
+> [!CAUTION]
+> This package is deprecated since v3.2.3. Please use one of the following alternatives:
 > - [`ic-use-internet-identity`](https://www.npmjs.com/package/ic-use-internet-identity)
 > - [`@ic-reactor/react`](https://www.npmjs.com/package/@ic-reactor/react)
-
-`@dfinity/use-auth-client`! This is a package for Internet Computer React developers, making it easier to integrate the auth-client with your React application.
-
-You can use it to manage your identity for you, or you can pass it an `idlFactory` and `canisterId` and it will construct and manage your entire `Actor` for you.
-
-Do you want to know more about developing on the Internet Computer? Visit the [Developer Docs](https://internetcomputer.org/docs/home).
-
-Additional API Documentation can be found [here](https://js.icp.build/core/v3.2/libs/use-auth-client/api).
-
----
-
-## Installation
-
-To install, use:
-
-```shell
-npm install @dfinity/use-auth-client
-```
-
-and you can import and set it up like so:
-
-```ts
-import {useAuthClient} from '@dfinity/use-auth-client';
-
-...ts
-const App = () => {
-  const identityProvider =
-    // eslint-disable-next-line no-undef
-    process.env.DFX_NETWORK === 'local'
-      ? // eslint-disable-next-line no-undef
-        `http://${process.env.CANISTER_ID_INTERNET_IDENTITY}.localhost:4943`
-      : 'https://identity.internetcomputer.org';
-
-  const { isAuthenticated, login, logout, actor } = useAuthClient({
-    loginOptions: {
-      identityProvider,
-    },
-    actorOptions: {
-      canisterId,
-      idlFactory,
-    },
-  });
-  ...
-}
-```
-
-## Multiple Actors
-
-If you have multiple actors, you can pass a record of `actorOptions` to the `useAuthClient` hook. The keys of the record will be the names of the actors, and the values will be the `actorOptions` for that actor. It will look something like this:
-
-```ts
-const { isAuthenticated, login, logout, actors } = useAuthClient({
-  actors: {
-    actor1: {
-      canisterId: canisterId1,
-      idlFactory: idlFactory1,
-    },
-    actor2: {
-      canisterId: canisterId2,
-      idlFactory: idlFactory2,
-    },
-  },
-});
-
-const { actor1, actor2 } = actors;
-```
-
-There is a live demo at https://5ibdo-haaaa-aaaab-qajia-cai.icp0.io/.