feat(xref): wider panel default, Attach DWG/Image/PDF menu, status icons

External References dock default 360 to 460 for the column-rich table. Attach split button reads Attach DWG with Attach Image and Attach PDF options, all menu rows full width. List view shows one distinct glyph and theme color per reference status.

locales/it-IT/opencadstudio.ftl

@@ -3204,6 +3204,8 @@ insert =
     .xref-new-path-for-selection = nuovo percorso per la selezione
     .xref-new-path-prefix = nuovo prefisso percorso
     .xref-old-path-prefix = vecchio prefisso percorso
+    .xref-attach-dwg = Attach DWG
+    .xref-attach-image = Attach Image
     .xref-save-the-drawing-first-to-resolve-relativ = XREF Salvare prima il disegno per risolvere i percorsi XREF relativi.
     .object-s-copied-to-clipboard-base-3-3 = Oggetto/i __ocs_fmt_0__ copiati negli appunti (base __ocs_fmt_1__,__ocs_fmt_2__).
     .object-s-copied-to-clipboard = __ocs_fmt_0__ oggetto/i copiati negli appunti.