Deliver each drop to the zone under the cursor (#953)

app/MindWork AI Studio/Dialogs/ChatTemplateDialog.razor

@@ -3,6 +3,10 @@
 
 <MudDialog>
     <DialogContent>
+        @* A drop anywhere in this dialog belongs to the dialog, not to the page behind it: *@
+        @* The name for the drop state is given although nobody uses it: the messages of this dialog
+           are listed in a table, whose rows would otherwise ask for the same name. *@
+        <PathDropZone IsArea="@true" Context="isDropTarget">
         <MudJustifiedText Class="mb-3" Typo="Typo.body1">
             @T("Create your custom chat template to tailor the LLM's behavior for specific tasks or domains. Define a custom system prompt and provide an example conversation to design an AI experience perfectly suited to your requirements.")
         </MudJustifiedText>
@@ -57,7 +61,7 @@
             <MudButton Class="mb-3" Color="Color.Default" OnClick="@this.UseDefaultSystemPrompt" StartIcon="@Icons.Material.Filled.ListAlt" Variant="Variant.Filled" Disabled="@this.IsReadOnly">
                 @T("Use the default system prompt")
             </MudButton>
-            <ReadFileContent Text="@T("Load system prompt from file")" @bind-FileContent="@this.DataSystemPrompt" Disabled="@this.IsReadOnly"/>
+            <ReadFileContent Text="@T("Load system prompt from file")" @bind-FileContent="@this.DataSystemPrompt" EnableDragDrop="true" Disabled="@this.IsReadOnly"/>
 
             <MudText Typo="Typo.h6" Class="mb-3 mt-6">
                 @T("Predefined User Input")
@@ -81,6 +85,7 @@
                 HelperText="@T("Tell the AI your predefined user input.")"
                 ReadOnly="@this.IsReadOnly"
             />
+            <ReadFileContent Text="@T("Load predefined user input from file")" @bind-FileContent="@this.PredefinedUserPrompt" EnableDragDrop="true" Disabled="@this.IsReadOnly"/>
 
             <MudText Typo="Typo.h6" Class="mb-3 mt-6">
                 @T("File Attachments")
@@ -90,10 +95,8 @@
             </MudJustifiedText>
             <AttachDocuments
                 Name="ChatTemplateFileAttachments"
-                Layer="@DropLayers.DIALOGS"
                 @bind-DocumentPaths="@this.fileAttachments"
                 UseSmallForm="false"
-                CatchAllDocuments="true"
                 ValidateMediaFileTypes="false"
                 Disabled="@this.IsReadOnly"
             />
@@ -202,6 +205,7 @@
         }
 
         <Issues IssuesData="@this.dataIssues"/>
+        </PathDropZone>
     </DialogContent>
     <DialogActions>
         @if (this.IsReadOnly)