Add docs for build order support in app (#11774)

docs/docs/app/build.md

@@ -0,0 +1,35 @@
+---
+title: Build Orders
+---
+
+## Build Order List
+
+The build order list display lists all build orders:
+
+{{ image("app/build_list.png", "Build order list") }}
+
+Select an individual build order to display the detail view for that order.
+
+### Filtering
+
+Displayed build orders can be subsequently filtered using the search input at the top of the screen
+
+## Build Order Detail
+
+{{ image("app/build_detail.png", "Build order detail") }}
+
+### Edit Build Order Details
+
+From the detail view, select the *Edit* button in the top-right of the screen. This opens the build order editing display.
+
+### Required Parts Tab
+
+The *Required Parts* tab shows the parts required to complete this build order:
+
+{{ image("app/build_required_parts.png", "Build order required parts") }}
+
+### Build Outputs Tab
+
+The *Build Outputs* tab shows the stock items which have been produced as part of this build order:
+
+{{ image("app/build_outputs.png", "Build order outputs") }}