[LVGL] Add "Cache font definitions" option to speed up project loading #962
Description
Studio uses lv_font_conv to extract both binary and source file definitions for fonts. When a project contains many user-defined fonts, or when a font includes a large number of characters (such as Chinese fonts), this extraction process can take considerable time. To address this, we should add a "Cache font definitions" option under Settings → General. When enabled, extracted font data will be cached in a file named .eez-project-fonts-cache, avoiding redundant extraction on subsequent loads. This option should be disabled by default, with users encouraged to enable it if project loading becomes noticeably slow.
