Moved plugins and add loaded file filtering

- Moved prettify_json and lsp_completer plugins to sub categories
- Add filter_out_loaded_files to prevent opening already-loaded files
- Refactor code events into single events module
- Fix signal blocking during file load operations
- Include READONLY state in source view lifecycle handling

src/libs/dto/code/events/text_changed_event.py

@@ -0,0 +1,18 @@
+# Python imports
+from dataclasses import dataclass, field
+
+# Lib imports
+
+# Application imports
+from .code_event import CodeEvent
+
+
+
+@dataclass
+class TextChangedEvent(CodeEvent):
+    has_selection: bool = False
+    start_range: int    = 0
+    end_range: int      = 0
+    line: int           = 0
+    char: int           = 0
+    value: str          = ""