Add file external deletion detection and improve WebKit UI

- Implement FileExternallyDeletedEvent handling with visual feedback
  via "file-deleted" CSS class on tabs
- Fix drag-and-drop to properly handle URI data
- Improve SourceFile.load() to use freeze_notify and proper buffer
  replacement instead of cursor insertion
- Add Developer Tools context menu option to WebKit view
- Relocate webkit_ui_settings from settings/other to settings/webkit

src/libs/dto/code/__init__.py

@@ -6,6 +6,8 @@
 from .code_event import CodeEvent
 from .register_provider_event import RegisterProviderEvent
 from .register_command_event import RegisterCommandEvent
+from .file_externally_modified_event  import FileExternallyModifiedEvent
+from .file_externally_deleted_event  import FileExternallyDeletedEvent
 
 from .get_new_command_system_event import GetNewCommandSystemEvent
 from .request_completion_event import RequestCompletionEvent

src/libs/dto/code/file_externally_deleted_event.py

@@ -0,0 +1,13 @@
+# Python imports
+from dataclasses import dataclass, field
+
+# Lib imports
+
+# Application imports
+from .code_event import CodeEvent
+
+
+
+@dataclass
+class FileExternallyDeletedEvent(CodeEvent):
+    ...

src/libs/dto/code/file_externally_modified_event.py

@@ -0,0 +1,13 @@
+# Python imports
+from dataclasses import dataclass, field
+
+# Lib imports
+
+# Application imports
+from .code_event import CodeEvent
+
+
+
+@dataclass
+class FileExternallyModifiedEvent(CodeEvent):
+    ...

src/libs/settings/webkit/webkit_ui_settings.py

@@ -95,7 +95,7 @@ class WebkitUISettings(WebKit2.Settings):
         self.set_property('javascript-can-open-windows-automatically', False)
 
         # Debugging
-        self.set_property('enable-developer-extras', False)
+        self.set_property('enable-developer-extras', True)
         self.set_property('enable-write-console-messages-to-stdout', False)
         self.set_property('draw-compositing-indicators', False)
         self.set_property('enable-mock-capture-devices', False)