Allow customizing font family of canvas elements from panel edit menu

**Why is this needed**: Currently, it is not possible to customize the font family for canvas elements through the panel edit menu. This limitation restricts users who want a consistent or branded look across their dashboards, or need specific fonts for accessibility or localization reasons. **What would you like to be added**: Add support in the panel edit menu to allow users to select and customize the font family for canvas elements. This should provide a user-friendly way to specify the font family, either by choosing from a predefined list or by entering a custom font. **Who is this feature for?** This feature would be valuable for dashboard designers, organizations with specific branding requirements, and users with font accessibility needs.