refactor(lsp): replace LSPManager with controller-based architecture

- Remove legacy LSPManager dialog implementation
- Introduce LSPController as the central LSP entry point
- Route UI interactions through lsp_controller.lsp_manager_ui
- Move client lifecycle handling out of ProviderResponseCache
- Simplify completion cache and matcher filtering
- Improve LSP completion item parsing with safer fallbacks
- Modernize typing (Python 3.10 union syntax)
- Remove unused imports and dead code
- Use GLib.idle_add for safe UI scrolling operations
- Minor comment and spelling fixes

plugins/code/completers/python_completer/provider.py

@@ -38,7 +38,7 @@ class Provider(GObject.GObject, GtkSource.CompletionProvider):
         iter.backward_char()
 
         ch = iter.get_char()
-        # NOTE: Look to re-add or apply supprting logic to use spaces
+        # NOTE: Look to re-add or apply supporting logic to use spaces
          # As is it slows down the editor in certain contexts...
         # if not (ch in ('_', '.', ' ') or ch.isalnum()):
         if not (ch in ('_', '.') or ch.isalnum()):