Update chat init args schema and improve security of auth docs (#138)

_snippets/chat/customization.mdx

@@ -5,21 +5,43 @@ Plain.init({
   // Optional. Hides the launcher, you can manually show it by calling `Plain.open()` (default: false)
   hideLauncher: false,
 
-  // Optional. The title of the chat window shown on the Welcome screen
-  title: 'Chat with us',
-
   // Optional. A collection of links shown on the Welcome screen
   links: [
     {
-      icon: 'book', // Optional, we also support 'discord' and 'slack' as icons
+      // Optional, supported icons are:
+      //   'bell',
+      //   'book',
+      //   'bug',
+      //   'bulb',
+      //   'chat',
+      //   'integration',
+      //   'discord',
+      //   'email',
+      //   'slack',
+      //   'link',
+      //   'pencil',
+      //   'send',
+      //   'support',
+      //   'error'
+      icon: 'book', 
       text: 'View our docs',
       url: 'https://www.plain.com/docs',
     },
   ],
 
-  // Optional. The entry point of the Chat, is either 'default' or 'chat'
-  // 'chat' will open the last conversation the user had (default: 'default')
-  entryPoint: 'default',
+  // Optional. The entry point of the Chat.
+  entryPoint: {
+    // Type is either 'default' or 'chat'. 'default' will open the intro screen, 'chat' opens up straight into a chat.
+    type: 'chat',
+    //  Optional. The external ID of which chat to open. If not provided it will default to the last conversation the user had
+    externalId: 'example_external_id',
+    // Optional. Prevents the user from going back to the intro screen to start a new chat
+    singleChatMode?: false,
+  },
+
+  // Optional. Lets you specify which HTML element to insert the chat into.
+  // When specified, launcher will be hidden by default.
+  embedAt: '#embed',
 
   // Optional. The color scheme of the Chat, is either 'auto', 'light', or 'dark'
   // 'auto' uses the user's browser preference to decide between light and dark mode (default: 'auto')
@@ -28,8 +50,80 @@ Plain.init({
   // Optional. Various styling options
   // Colors can also be passed in this format { light: '#FFFFFF', dark: '#000000' }. Based on the theme chosen by you or browser preference
   style: {
-    chatButtonColor: '#000000'; // These can also be passed in this foramt { light: '#FFFFFF', dark: '#000000' }
-    chatButtonIconColor: '#FFFFFF';
+    launcherBackgroundColor: '#000000'; // These can also be passed in this format { light: '#FFFFFF', dark: '#000000' }
+    launcherIconColor: '#FFFFFF';
   }
+
+  // Optional. Logo which is shown in the header of the chat intro screen
+  logo: {
+    // url to get the logo from
+    url: 'http://example.com';
+    // Optional. Alt text which is displayed on hover of the logo
+    alt: 'An example logo';
+  };
+
+  // Optional. Allows you to set fields for the threads which are created from chats
+  threadDetails: {
+
+    // Optional. Labels to be set on created threads. 
+    // To find a label id open the Plain app and go to 'Settings' -> 'Labels', you can select `Copy label ID` from the overflow menu on each label
+    labelTypeIds: ['lt_01JDAB92EBHP3DSXS43DW96WBS'],
+
+    // Optional. A tier to be set on created threads.
+    // To find a tier ID open the Plain app and go to 'Settings' -> 'Tiers'. Select a tier and then copy the ID from the URL.
+    // You can also specify a tier by its external ID e.g { externalId: 'example_external_id' }
+    tierIdentifier: { tierId: 'tier_01JDABCAZBDFKH7WA6WNBDSA2F' },
+
+    // Optional. A tenant to be set on created threads.
+    // To find a tenant ID open the Plain app and click 'Tenants' under 'Browse' in the left sidebar. Select a tenant and then copy the ID from the URL.
+    // You can also specify a tenant by its external ID e.g { externalId: 'example_external_id' }
+    tenantIdentifier: { tenantId: 'te_01HT539973HNVZFSDXWHPT8FH1' },
+
+    // Optional. An external ID to be set on created threads.
+    externalId: 'example_external_id';
+  };
+
+  // Optional. Lets you customize the buttons which are used to start a new chat on the intro screen
+  chatButtons: [
+    {
+      // Optional. The name of the icon to display, see above for full options
+      icon: 'bulb',
+
+      // The text to display on the button
+      text: 'Give feedback',
+
+      // Optional. Allows you to set fields for the threads which are created with this button. See above for full options.
+      threadDetails: {};
+
+      // Optional. Form elements which the user must fill out before sending a chat message
+      form: {
+
+        // The fields which make up the form. All form fields must be filled in for a user to send a chat message
+        fields: [
+          {
+            // Currently only dropdown form fields are supported
+            type: 'dropdown',
+
+            // Optional. The placeholder text displayed on the dropdown
+            placeholder: 'Select a topic...',
+
+            // The options which are available in the dropdown, minimum of 1 required.
+            options: [
+              {
+                // Optional. An icon to be displayed on the dropdown option. See above for full options.
+                icon: 'bug',
+
+                // The text which is displayed for this dropdown option
+                text: 'Bug report',
+
+                // Optional. Enables setting values on threads when this option is selected by the user. See above for full options
+                threadDetails: {},
+              }
+            ],
+          }
+        ]
+      },
+    }
+  ];
 });
 ```

chat.mdx

@@ -13,9 +13,8 @@ Here’s how to get started:
 
 <Steps>
   <Step title="Create your Chat app">
-    *At the moment you can only create a single Chat app configuration per workspace. In future we
-    will allow multiple configurations.* - In Plain, navigate to **`Settings`** > **`Chat`**. -
-    Press **`Create Chat App`**.
+    In Plain, navigate to **`Settings`** > **`Chat`**. 
+    Press **`Create a Chat App`**.
   </Step>
   <Step title="Add Chat to your webpage(s)">
     After creating your Chat app, you will be provided with a snippet of code that you can embed in

chat/authentication.mdx

@@ -24,7 +24,9 @@ These details will be shown to you in the Plain app when you are chatting with t
 If you want to match the customer to an existing customer in your workspace, you will need to pass their email. To avoid security issues around impersonation you will also need to
 provide the email address hashed using a shared secret. You can generate this secret in the Chat settings page in the Plain app.
 
-Once you have this secret, you can calculate the hash and pass it to the `Plain.init` function:
+Once you have this secret, you can calculate the hash. This must be done in backend code to avoid leaking the secret. If your secret is leaked malicious users will be able to impersonate your customers in chats.
+
+Backend code:
 
 ```typescript
 import * as crypto from 'node:crypto';
@@ -34,6 +36,13 @@ const email = '[email protected]';
 const hmac = crypto.createHmac('sha256', secret);
 hmac.update(email);
 const hash = hmac.digest('hex');
+```
+
+Then you can request the hash from your backend and init Plain:
+
+```typescript
+const email = '[email protected]';
+const hash = fetchHashFromBackend(email);
 
 Plain.init({
   customerDetails: {