feat(docs): add admin center docs (#9646)

* add admin center docs

* add basic system settings docs

docs/docs/settings/admin.md

@@ -1,17 +1,43 @@
 ---
-title: InvenTree Admin Interface
+title: InvenTree Admin Interfaces
 ---
 
-## Admin Interface
+There are multiple administration interfaces available in InvenTree, which provide different levels of access to the underlying resources and different operational safety.
 
-Users which have *staff* privileges have access to an Admin interface which provides extremely low level control of the database. Every item in the database is available and this interface provides a convenient option for directly viewing and modifying database objects.
+- Admin Center - Main interface for managing InvenTree - Robust verification and safety checks
+- System Settings - Access to all settings - Robust verification, requires reading the documentation
+- Backend Admin Interface - Low level access to the database - Few verification or safety checks
+
+### Admin Center
+
+The Admin Center is the main interface for managing InvenTree. It provides a user-friendly interface for managing all aspects of the system, including:
+- Users / Groups
+- Data import / export
+- Customisation (e.g. project codes, custom states, parameters and units)
+- Operational controls (e.g. background tasks, errors, currencies)
+- Integration with external services (via machines and plugins)
+- Reporting and statistics
+
+It can be access via the *Admin Center* link in the top right user menu, the *Admin Center* quick-link in the command palette, or via the navigation menu.
+
+#### Permissions
+
+Some panes can only be accessed by users with specific permissions. For example, the *Stocktake* pane can only be accessed by users with the `stocktake` permission.
+
+### System Settings
+
+The System Settings interface provides ordered access to all global settings in InvenTree. Users need to have _staff_ privileges enabled or the _a:staff_ scope.
+
+### Backend Admin Interface
+
+Users which have *staff* privileges have access to an Admin interface which provides extremely low level control of the database. Every item in the database is available and this interface provides a unrestricted option for directly viewing and modifying database objects.
 
 !!! warning "Caution"
 	Admin users should exercise extreme care when modifying data via the admin interface, as performing the wrong action may have unintended consequences!
 
 The admin interface allows *staff* users the ability to directly view / add / edit / delete database entries according to their [user permissions](./permissions.md).
 
-### Access Admin Interface
+#### Access Backend Admin Interface
 
 To access the admin interface, select the "Admin" option from the drop-down user menu in the top-right corner of the screen.
 
@@ -28,7 +54,7 @@ An administration panel will be presented as shown below:
 !!! info "Admin URL"
     To directly access the admin interface, append /admin/ to the InvenTree site URL - e.g. http://localhost:8000/admin/
 
-### View Database Objects
+#### View Database Objects
 
 Database objects can be listed and filtered directly. The image below shows an example of displaying existing part categories.
 
@@ -39,7 +65,7 @@ Database objects can be listed and filtered directly. The image below shows an e
 !!! info "Permissions"
     A "staff" account does not necessarily provide access to all administration options, depending on the roles assigned to the user.
 
-#### Filtering
+##### Filtering
 
 Some admin views support filtering of results against specified criteria. For example, the list of Part objects can be filtered as follows:
 
@@ -47,7 +73,7 @@ Some admin views support filtering of results against specified criteria. For ex
 {% include 'img.html' %}
 {% endwith %}
 
-### Edit Database Objects
+#### Edit Database Objects
 
 Individual database objects can be edited directly in the admin interface. The image below shows an example of editing a Part object:
 

docs/docs/settings/import.md

@@ -27,7 +27,7 @@ Importing data is a multi-step process, which is managed via an *import session*
 
 The import session is managed by the InvenTree server, and all import session data is stored on the server. As the import process can be time-consuming, the user can navigate away from the import page and return later to check on the progress of the import.
 
-Import sessions can be managed from the *Admin Center* page, which lists all available import sessions
+Import sessions can be managed from the [Admin Center](./admin.md#admin-center) page, which lists all available import sessions
 
 ### Context Sensitive Importing