Schnittlinien-Werkzeug: Befehl sectionline/viewline setzt linePoints

Zwei Klicks (Start -> Ende) legen die Grundriss-Schnitt-/Ansichtslinie einer
DrawingLevel fest. Ziel: genau eine Platzhalter-Ebene ohne Linie wird belegt,
sonst neue Ebene (Schnitt B/C ...). Live-Vorschau mit Richtungspfeil, Art
(Schnitt/Ansicht) als Inline-Option umschaltbar. Registry-Aliase schnittlinie/
ansichtslinie, Ribbon-Gruppe 'Schnitte' im BIM-Tab, i18n de/en, Datenpfad-Tests.

src/i18n/de.ts

@@ -145,6 +145,7 @@ export const de = {
   "ribbon.group.draw": "Zeichnen",
   "ribbon.group.modify": "Ändern",
   "ribbon.group.components": "Bauteile",
+  "ribbon.group.sections": "Schnitte",
   "ribbon.group.custom": "Eigene Leiste",
   "ribbon.custom.add": "＋ Hinzufügen",
   "ribbon.custom.empty": "Elemente über ＋ Hinzufügen wählen",
@@ -974,6 +975,13 @@ export const de = {
   "cmd.roof.shape.mansarde": "Mansarddach",
   "cmd.roof.shape.zelt": "Zeltdach",
   "cmd.roof.shape.flach": "Flachdach",
+  "cmd.sectionline.label": "Schnittlinie",
+  "cmd.sectionline.start": "Schnitt-Startpunkt:",
+  "cmd.sectionline.end": "Schnitt-Endpunkt:",
+  "cmd.sectionline.kind.section": "Schnitt",
+  "cmd.sectionline.kind.elevation": "Ansicht",
+  "cmd.sectionline.newSection": "Schnitt {letter}",
+  "cmd.sectionline.newElevation": "Ansicht {letter}",
   "cmd.opening.label": "Öffnung",
   "cmd.opening.windowLabel": "Fenster",
   "cmd.opening.doorLabel": "Tür",

src/i18n/en.ts

@@ -144,6 +144,7 @@ export const en: Record<TranslationKey, string> = {
   "ribbon.group.draw": "Draw",
   "ribbon.group.modify": "Modify",
   "ribbon.group.components": "Components",
+  "ribbon.group.sections": "Sections",
   "ribbon.group.custom": "Custom bar",
   "ribbon.custom.add": "＋ Add",
   "ribbon.custom.empty": "Pick elements via “＋ Add”",
@@ -964,6 +965,13 @@ export const en: Record<TranslationKey, string> = {
   "cmd.roof.shape.mansarde": "Mansard roof",
   "cmd.roof.shape.zelt": "Pyramid roof",
   "cmd.roof.shape.flach": "Flat roof",
+  "cmd.sectionline.label": "Section line",
+  "cmd.sectionline.start": "Section start point:",
+  "cmd.sectionline.end": "Section end point:",
+  "cmd.sectionline.kind.section": "Section",
+  "cmd.sectionline.kind.elevation": "Elevation",
+  "cmd.sectionline.newSection": "Section {letter}",
+  "cmd.sectionline.newElevation": "Elevation {letter}",
   "cmd.opening.label": "Opening",
   "cmd.opening.windowLabel": "Window",
   "cmd.opening.doorLabel": "Door",