Clean up deprecated code and fix multiple issues

- Remove deprecated markdown_preview plugin and re-wrote
- Renamed alt_provider.py under words completer
- Fix words completion provider logic and cache handling
- Fix container orientations (VERTICAL -> HORIZONTAL) and add Separators
- Remove unused Gtk imports from search_replace plugin
- Fix event creation parameter order in source_file.py
- Fix typo in source_view.py (_load_pretify_json -> _load_prettify_json)
- Refactor webkit_ui with new load methods and enhanced settings

plugins/code/markdown_preview/plugin.py

@@ -0,0 +1,56 @@
+# Python imports
+
+# Lib imports
+
+# Application imports
+from libs.event_factory import Event_Factory, Code_Event_Types
+
+from plugins.plugin_types import PluginCode
+
+from .markdown_preview import MarkdownPreview
+
+
+
+markdown_preview = MarkdownPreview()
+
+
+
+class Plugin(PluginCode):
+    def __init__(self):
+        super(Plugin, self).__init__()
+
+
+    def _controller_message(self, event: Code_Event_Types.CodeEvent):
+        if isinstance(event, Code_Event_Types.FocusedViewEvent):
+            markdown_preview._do_markdown_translate(event.view.get_buffer())
+        elif isinstance(event, Code_Event_Types.TextChangedEvent):
+            markdown_preview._do_markdown_translate(event.buffer)
+
+    def load(self):
+        separator_right  = self.requests_ui_element("separator-right")
+        markdown_preview.set_relative_to(separator_right)
+
+        event = Event_Factory.create_event("register_command",
+            command_name = "tggle_markdown_preview",
+            command      = Handler,
+            binding_mode = "released",
+            binding      = "<Shift><Control>m"
+        )
+
+        self.message_to("source_views", event)
+
+    def run(self):
+        ...
+
+ 
+class Handler:
+    @staticmethod
+    def execute(
+        view: any
+    ):
+        logger.debug("Command: Markdown Preview")
+
+        if not markdown_preview.can_hide:
+            markdown_preview.can_hide = True
+
+        markdown_preview.popdown() if markdown_preview.is_visible() else markdown_preview.popup()