M7: the Small caps sample in Type settings draws without a box

The Small caps button in Type settings labelled itself "Aɢ", but the
small-capital G (U+0262) is missing from egui's default fonts, which the
UI uses whenever Inter isn't built in, so the button showed "A" and a box.
The sample is now a capital followed by smaller capitals laid out from
ordinary letters every UI font has. A test checks the UI fonts draw every
letter of the sample.

docs/roadmap.md

@@ -73,6 +73,7 @@ blockers.
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-14 | minor | M7: the Small caps button in Type settings showed a box where the UI font has no small-capital `ɢ` (builds without Inter use egui's fonts); its sample is now a capital and a smaller capital, drawn from ordinary letters every UI font has. Numbers unchanged |
 | 2026-10-14 | minor | M7: Home screen recent files as cards: each card shows the picture its file carries on its first page's colour, the file's icon, name and "Edited ... ago"; sort by name, creation or last change either way; a table view; a click selects, a double-click or Enter opens, arrow keys move; Open, Show in folder and Remove from recents on right-click. Numbers unchanged. |
 | 2026-10-14 | minor | Lost images reported on loading (#207): a `.figcraft` file whose image member is damaged, too large or missing no longer loads in silence; each lost image (up to 20, then a count) is listed in `repairs` on `file.open` with its hash and the reason, and the app shows it as a toast. Saving still writes the file without the lost images. Numbers unchanged |
 | 2026-10-14 | minor | SVG import budgets (#190): gzipped SVG is unpacked by FigCraft within 64 MiB before parsing (it was unpacked without a limit), so the nesting check sees the real document; SVG documents embedded in `<image>` data URIs share one 32 MiB budget and at most 4 levels, and one past a budget is left out. Linked files stay unread. Numbers unchanged |