Fix createMultiDimConfig grapher config logic

We need to store all of the mdim related config in the patch config
saved in the DB so we can use it to perform chart config updates, e.g.
when the variable config changes in admin or ETL.

adminSiteServer/multiDim.ts

@@ -281,29 +281,34 @@ export async function createMultiDimConfig(
         slug
     )
     const reusedChartConfigIds = new Set<string>()
+    const { grapherConfigSchema } = config
 
     const enrichedViews = await Promise.all(
         config.views.map(async (view) => {
             const variableId = view.indicators.y[0]
-            let patchGrapherConfig = {}
+            // Main config for each view.
+            const mainGrapherConfig = {
+                $schema:
+                    "https://files.ourworldindata.org/schemas/grapher-schema.005.json",
+                dimensions: MultiDimDataPageConfig.viewToDimensionsConfig(view),
+                selectedEntityNames: config.defaultSelection ?? [],
+            }
+            let viewGrapherConfig = {}
             if (view.config) {
-                patchGrapherConfig = config.grapherConfigSchema
+                viewGrapherConfig = grapherConfigSchema
                     ? migrateGrapherConfigToLatestVersion({
                           ...view.config,
-                          $schema: config.grapherConfigSchema,
+                          $schema: grapherConfigSchema,
                       })
                     : view.config
             }
+            const patchGrapherConfig = mergeGrapherConfigs(
+                viewGrapherConfig,
+                mainGrapherConfig
+            )
             const fullGrapherConfig = mergeGrapherConfigs(
                 variableConfigs.get(variableId) ?? {},
-                patchGrapherConfig,
-                {
-                    $schema:
-                        "https://files.ourworldindata.org/schemas/grapher-schema.005.json",
-                    dimensions:
-                        MultiDimDataPageConfig.viewToDimensionsConfig(view),
-                    selectedEntityNames: config.defaultSelection ?? [],
-                }
+                patchGrapherConfig
             )
             const existingChartConfigId = existingViewIdsToChartConfigIds.get(
                 dimensionsToViewId(view.dimensions)