refactor: update markdown dependencies and enhance rendering capabilities

- Added flutter_markdown_plus as a new dependency for improved markdown rendering.
- Removed deprecated markdown_widget and related LaTeX handling, streamlining the codebase.
- Updated the ConduitMarkdown class to utilize the new markdown processing logic, enhancing maintainability.
- Improved the StreamingMarkdownWidget to leverage the updated markdown rendering methods, ensuring a cohesive user experience.
- Enhanced support for LaTeX and Mermaid diagrams within markdown content, providing better visual representation.

pubspec.yaml

@@ -29,12 +29,15 @@ dependencies:
   hive_ce_flutter: ^2.3.2
   shared_preferences: ^2.3.2
   
-  # UI Components - GPT Markdown  
+  # UI Components - Markdown Rendering
   cached_network_image: ^3.3.1
   flutter_highlight: ^0.7.0
+  flutter_markdown_plus: ^1.0.5
+  markdown: ^7.3.0
   webview_flutter: ^4.7.0
   socket_io_client: ^3.1.2
   yaml: ^3.1.2
+  flutter_math_fork: ^0.7.4
   
   
   
@@ -65,9 +68,6 @@ dependencies:
   share_plus: ^12.0.0
   share_handler: ^0.0.19
   riverpod_annotation: ^3.0.0
-  markdown_widget: ^2.3.2+8
-  flutter_math_fork: ^0.7.4
-  markdown: ^7.3.0
   
   # Clipboard functionality is available through flutter/services (part of Flutter SDK)