Merge upstream/master (COSMIC 1.6) into main

Aligne le fork sur epoch-1.6.0 (63 commits amont) en preservant les 19
commits yoda.

Resolutions notables :
- les cfg `all(feature = "wayland", target_os = "linux")` deviennent
  l alias `wayland_platform` introduit en amont ; il exclut winit comme
  le faisait le patch yoda 45eaaf16, l intention est donc preservee ;
- les features iced `cctk` ont ete renommees `wayland` en amont, la
  feature `wayland` locale est adaptee ; `winit` reste un marqueur vide
  et `iced/winit` est liste explicitement ;
- cctk/ashpd gardent leurs chemins locaux dans la section conditionnelle
  unix introduite en amont ;
- la garde anti-crash c0b653f5 (context_menu non assigne) est conservee
  par-dessus la nouvelle structure amont ;
- traductions ca/oc restaurees depuis amont.

Le submodule iced suit (merge + correctif du cfg cctk residuel).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

i18n/ca/libcosmic.ftl

@@ -0,0 +1,3 @@
+license = Llicència
+close = Tancar
+links = Enllaços

i18n/gl/libcosmic.ftl

@@ -0,0 +1,34 @@
+close = Pechar
+license = Licenza
+links = Enderezos
+developers = Desenvolvedores
+designers = Deseñadores
+artists = Artistas
+translators = Traductores
+documenters = Documentadores
+january = Xaneiro { $year }
+february = Febreiro { $year }
+march = Marzo { $year }
+april = Abril { $year }
+may = Maio { $year }
+june = Xuño { $year }
+july = Xullo { $year }
+august = Agosto { $year }
+september = Setembro { $year }
+october = Outubro { $year }
+november = Novembro { $year }
+december = Decembro { $year }
+monday = Luns
+mon = Lun
+tuesday = Martes
+tue = Mar
+wednesday = Mércores
+wed = Mér
+thursday = Xoves
+thu = Xov
+friday = Venres
+fri = Ven
+saturday = Sábado
+sat = Sáb
+sunday = Domingo
+sun = Dom

i18n/oc/libcosmic.ftl

@@ -0,0 +1,14 @@
+monday = Diluns
+mon = Dil
+tuesday = Dimars
+tue = Dim
+wednesday = Dimècres
+wed = Dma
+thursday = Dijòus
+thu = Dij
+friday = Divendres
+fri = Div
+saturday = Dissabte
+sat = Dis
+sunday = Dimenge
+sun = Dim