build 219: wider toggle pill, transparent panel bg, shorter panel names

Resize handle toggle: 14px wide (centered over 4px handle) so the
arrow icon is clearly visible. File tree and outline backgrounds set
to transparent so the panel-group noise+gradient shows through.
FR: file_tree→"Fichiers", file_outline→"Plan" (+ hide variants).
IT: file_tree→"File", IT/ES hide keys shortened to match.
DE unchanged (Dateibaum/Gliederung already concise).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

services/web/frontend/stylesheets/pages/editor/ide-lumiere.scss

@@ -30,8 +30,8 @@ $lum-noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' wi
   --ide-rail-header-subdued-button-color: #2d5a52;
   --ide-rail-header-subdued-button-hover-background: rgba(42, 157, 143, 0.15);
 
-  // File tree
-  --file-tree-bg:                      #f4fbf9;
+  // File tree — transparent so the panel-group noise shows through
+  --file-tree-bg:                      transparent;
   --file-tree-item-color:              #1a2e3b;
   --file-tree-icon-colour:             #2a9d8f;
   --file-tree-expand-button-color:     #1a2e3b;
@@ -44,13 +44,13 @@ $lum-noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' wi
   --bg-accent-02: #{$lum-teal};
   --bg-accent-03: rgba(42, 157, 143, 0.15);
 
-  // Outline panel
-  --outline-bg-color:                   #f4fbf9;
+  // Outline panel — transparent bg so the panel-group noise shows through
+  --outline-bg-color:                   transparent;
   --outline-border-color:               #{$lum-border};
   --outline-header-hover-bg:            rgba(42, 157, 143, 0.08);
   --outline-item-hover-bg:              rgba(42, 157, 143, 0.10);
   --outline-line-guide-color:           #{$lum-border};
-  --outline-container-color-bg:         #f4fbf9;
+  --outline-container-color-bg:         transparent;
   --outline-content-color:              #1a2e3b;
   --outline-item-highlight-bg:          rgba(42, 157, 143, 0.20);
   --outline-item-highlight-color:       #1a5c52;
@@ -404,9 +404,12 @@ $lum-noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' wi
   }
 }
 
-// Collapse toggle pill — teal instead of grey
+// Collapse toggle pill — wider than the 4px handle so the arrow icon is visible
 [data-lumiere='true'] .custom-toggler {
-  background-color: rgba($lum-teal, 0.55);
+  width: 14px !important;
+  left: -5px; // center 14px pill over the 4px handle
+  border-radius: 4px;
+  background-color: rgba($lum-teal, 0.65);
 
   &:hover {
     background-color: $lum-teal;

services/web/locales/es.json

@@ -920,7 +920,7 @@
   "file_outline": "Esquema del archivo",
   "file_size": "Tamaño del archivo",
   "file_too_large": "Archivo demasiado grande",
-  "file_tree": "árbol de archivos",
+  "file_tree": "Archivos",
   "files_cannot_include_invalid_characters": "El nombre del archivo está vacío o contiene caracteres no válidos",
   "files_selected": "archivos seleccionados.",
   "filter_projects": "Filtrar proyectos",
@@ -1146,9 +1146,9 @@
   "hide_configuration": "Ocultar configuración",
   "hide_deleted_user": "Ocultar usuarios eliminados",
   "hide_document_preamble": "Ocultar preámbulo del documento",
-  "hide_file_tree": "Ocultar árbol de archivos",
+  "hide_file_tree": "Ocultar archivos",
   "hide_local_file_contents": "Ocultar el contenido del archivo local",
-  "hide_outline": "Ocultar esquema de archivo",
+  "hide_outline": "Ocultar esquema",
   "higher_ai_allowance": "Mayor asignación de IA",
   "history": "Historia",
   "history_add_label": "Agregar etiqueta",

services/web/locales/fr.json

@@ -919,10 +919,10 @@
   "file_name_in_this_project": "Nom du fichier dans ce projet",
   "file_name_in_this_project_figure_modal": "Nom du fichier dans ce projet",
   "file_or_folder_name_already_exists": "Un fichier ou un dossier portant ce nom existe déjà",
-  "file_outline": "Structure du fichier",
+  "file_outline": "Plan",
   "file_size": "Taille du fichier",
   "file_too_large": "Fichier trop volumineux",
-  "file_tree": "Arborescence des fichiers",
+  "file_tree": "Fichiers",
   "files_cannot_include_invalid_characters": "Le nom du fichier est vide ou contient des caractères invalides",
   "files_selected": "fichiers sélectionnés.",
   "filter_projects": "Filtrer les projets",
@@ -1148,9 +1148,9 @@
   "hide_configuration": "Masquer la configuration",
   "hide_deleted_user": "Masquer les utilisateurs supprimés",
   "hide_document_preamble": "Masquer le préambule du document",
-  "hide_file_tree": "Masquer l'arborescence des fichiers",
+  "hide_file_tree": "Masquer les fichiers",
   "hide_local_file_contents": "Masquer le contenu du fichier local",
-  "hide_outline": "Masquer la structure du fichier",
+  "hide_outline": "Masquer le plan",
   "higher_ai_allowance": "Allocation d'IA plus élevée",
   "history": "Historique",
   "history_add_label": "Ajouter étiquette",

services/web/locales/it.json

@@ -919,7 +919,7 @@
   "file_outline": "Schema del file",
   "file_size": "Dimensioni del file",
   "file_too_large": "File troppo grande",
-  "file_tree": "Albero dei file",
+  "file_tree": "File",
   "files_cannot_include_invalid_characters": "Il nome del file è vuoto o contiene caratteri non validi",
   "files_selected": "file selezionati.",
   "filter_projects": "Filtra progetti",
@@ -1145,9 +1145,9 @@
   "hide_configuration": "Nascondi configurazione",
   "hide_deleted_user": "Nascondi gli utenti eliminati",
   "hide_document_preamble": "Nascondi il preambolo del documento",
-  "hide_file_tree": "Nascondi l'albero dei file",
+  "hide_file_tree": "Nascondi i file",
   "hide_local_file_contents": "Nascondi il contenuto del file locale",
-  "hide_outline": "Nascondi la struttura del file",
+  "hide_outline": "Nascondi lo schema",
   "higher_ai_allowance": "Indennità AI più elevata",
   "history": "Storia",
   "history_add_label": "Aggiungi etichetta",