Add relationships as possible datasource for grid

packages/standard-components/src/DataGrid/Component.svelte

@@ -17,7 +17,7 @@
   export let _bb
   export let datasource = {}
   export let editable
-  export let theme = 'alpine'
+  export let theme = "alpine"
 
   let dataLoaded = false
   let data
@@ -33,6 +33,7 @@
     rowSelection: editable ? "multiple" : false,
     suppressRowClickSelection: !editable,
   }
+  let store = _bb.store
 
   onMount(async () => {
     if (datasource.modelId) {
@@ -40,7 +41,7 @@
       model = await jsonModel.json()
       const { schema } = model
       if (!isEmpty(datasource)) {
-        data = await fetchData(datasource)
+        data = await fetchData(datasource, $store)
         columnDefs = Object.keys(schema).map((key, i) => {
           return {
             headerCheckboxSelection: i === 0 && editable,