Graphic Attributes: quieter swatches, Enter in linetype scale, undo names

- Colour swatches carry no *VARIES* or ByBlock text; the L / B / C / V
  button already shows that.
- A separator sits between "Create Layer with active settings" and the
  "Create fills on the current layer" checkbox.
- The linetype scale field is a plain text field like the Properties
  panel: the first click selects its value, Enter applies it (decimal
  comma and expressions accepted) instead of repeating the last command.
  This drops the iced_aw number_input feature again.
- Undo/redo name fill changes "Fill change" and linetype changes
  "Linetype", in all 21 locales.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01VgkJN8DEojuPTumAXLHotu

src/locale_catalog.rs

@@ -5274,7 +5274,7 @@ pub(super) fn message_attribute(source: &str) -> Option<(&'static str, &'static
         "Graphic Attributes: 1 unsupported object was not changed." => Some(("graphic-attributes", "one-unsupported")),
         "Graphic Attributes: {skipped} unsupported objects were not changed." => Some(("graphic-attributes", "unsupported-skipped")),
         "Fill transparency" => Some(("graphic-attributes", "fill-transparency")),
-        "Line linetype" => Some(("graphic-attributes", "line-linetype")),
+        "Fill change" => Some(("graphic-attributes", "fill-change")),
         "Line transparency" => Some(("graphic-attributes", "line-transparency")),
         "Cyl." => Some(("graphic-attributes", "cylindrical-short")),
         "Spher." => Some(("graphic-attributes", "spherical-short")),