TW-984: Add the documentation for configuration app grid

docs/configurations/app_grid_configuration.md

@@ -0,0 +1,49 @@
+## Configuration for App Grid
+
+### Context
+- Twake Chat is a service inside Twake Workspace which include other services
+- User need to access other services from Twake Chat
+- Just only support for web version
+
+### How to config
+
+1. Add services to configuration file
+
+- Each service have the information:
+```
+    {
+      "appName": "Twake Chat",
+      "icon": "ic_twake_chat.svg",
+      "appLink": "https://beta.twake.app/",
+    }
+```
+
+- All services must be added to the configuration file [configurations\app_dashboard.json](https://github.com/linagora/twake-on-matrix/blob/main/configurations/app_dashboard.json)
+  For example:
+```
+{
+  "apps": [
+    {
+      "appName": "Twake Mail",
+      "icon": "ic_twake_mail.svg",
+      "appLink": "http://tmail.linagora.com/"
+    },
+    {
+      "appName": "Twake Chat",
+      "icon": "ic_twake_chat.svg",
+      "appLink": "https://beta.twake.app/"
+    },
+    ...
+  ]
+}
+```
+
+- `appName`: The name will be showed in App Grid
+- `icon`: Name of icon was added in `configurations\icons` folder
+- `appLink`: Service URL
+
+2. Enable it in [config.sample.json](https://github.com/linagora/twake-on-matrix/blob/main/config.sample.json)
+```
+app_grid_dashboard_available=true
+```
+If you want to disable it, please change the value to `false` or remove this from `config.sample.json`