i18n: add Ukrainian interface translation (#36)

Rebase onto main: the interface language is saved with main's other
preferences (cadcraft.prefs, beside the theme) instead of its own storage
key, on desktop and web; strings main added or changed in the touched
places (Dynamic Input settings, Properties header and current-property
rows, block picker, theme and command-history menu items, open/save
filters) are wrapped and translated; main's native-menu poll order is kept.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

Cargo.lock

@@ -551,6 +551,7 @@ dependencies = [
  "muda",
  "rfd",
  "serde_json",
+ "sys-locale",
  "winit",
  "winresource",
 ]
@@ -3382,6 +3383,15 @@ dependencies = [
  "syn 3.0.6",
 ]
 
+[[package]]
+name = "sys-locale"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8eab9a99a024a169fe8a903cf9d4a3b3601109bcc13bd9e3c6fff259138626c4"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "tempfile"
 version = "3.27.0"