Sumra 0.2.9

Sumra 0.2.9 improves reading controls and EPUB cover rendering following issue #31.

• Custom Document Colors and Choose Theme display usable controls. Pure white paper can be selected with the Background color well; Use Theme restores the selected palette.
• Five distinct built-in themes replace the longer preset list: Light (pure white), Light Warm, Dark, Dracula and Gruvbox. Choose Theme previews the palette before applying. Customize saves named text, background and link colors, with color wells and precise RGB fields; saved themes can be edited or deleted. Previously saved preset IDs remain readable.
• The reading Font menu and default typography settings list available installed font families. Typography and CSS accepts a family name such as Iowan Old Style, including supplemental families macOS omits from that list. Install additional font files using macOS Font Book.
• Native reader arrow keys remain in the navigation path during page replacement, so rapid repeated presses continue to navigate. Text entry, sidebar controls and keyboard selection keep their own arrow behavior.
• SVG image and EPUB cover rendering preserve the authored aspect-ratio behavior across window sizes and reading layouts.

Original documents are not changed. The reporter's EPUB was not attached to the issue; representative cover fixtures and local original books are used for validation, and the issue remains open for feedback on the original file.