Enhance the shortcuts management in `Obsidean.cs` by introducing an "IsFavorite" column. Implement directory creation for markdown files if they don't exist, and update data structures to support the new column. Improve table data handling by filtering out non-data lines and ensuring consistent column counts during operations.
- Updated comments for clarity and corrected encoding issues.
- Added `LeerShortcuts` to read shortcuts from markdown files.
- Introduced `LeerShortcutsPorAplicacion` to filter shortcuts by application name.
- Implemented `AgregarOSobrescribirShortcut` for adding or overwriting shortcuts.
- Added `RemoveDoubleBrackets` utility method to clean up text.
- Enhanced readability of existing methods' comments.
Miguel