Add drawing workspace feature

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

도면작성/sheet.ts

@@ -0,0 +1,28 @@
+import { paperEntity, presentationEntities } from './presentation';
+import type { DrawingDocument, DrawingView, Entity, Point, Source } from './types';
+import { templateFrame } from './template';
+
+/** Paper-space entities in actual paper mm (origin bottom-left), shared by SVG and DXF Layout1. */
+export function viewPaperEntities(doc:DrawingDocument,view:DrawingView):{entity:Entity;index:number}[] {
+  const up=(p:Point):Point=>[p[0],p[1]+doc.paper.height];
+  return presentationEntities(view).map(({entity,index})=>{
+    const e=paperEntity(view,entity);
+    if(e.kind==='line')return{index,entity:{...e,a:up(e.a),b:up(e.b)}};
+    if(e.kind==='polyline')return{index,entity:{...e,points:e.points.map(up)}};
+    if(e.kind==='hatch')return{index,entity:{...e,points:e.points.map(up),holes:e.holes?.map(loop=>loop.map(up))}};
+    if(e.kind==='circle')return{index,entity:{...e,center:up(e.center)}};
+    if(e.kind==='text')return{index,entity:{...e,point:up(e.point)}};
+    throw new Error('Unexpected paper dimension');
+  });
+}
+export function sheetFrame(doc:DrawingDocument):Entity[] {
+  const out:Entity[]=templateFrame(doc),{width:w,height:h}=doc.paper,source:Source={member:'sheet',pier:doc.pier,index:0};
+  const p=(x:number,y:number):Point=>[x,h-y];
+  const line=(x0:number,y0:number,x1:number,y1:number)=>out.push({kind:'line',a:p(x0,y0),b:p(x1,y1),layer:'TEXT',source});
+  const text=(x:number,y:number,t:string,size=2.3,align:'left'|'center'='left')=>out.push({kind:'text',point:p(x,y),text:t,height:size,align,layer:'TEXT',source});
+  for(const view of doc.views){
+    if(['section','schedule','heights'].includes(view.id))continue;
+    text(view.slot.x,view.slot.y-3,`${view.title}${view.id==='keyplan'?'':`  1:${view.scale}`}${view.breaks?.length?' (생략)':''}`,3.0);
+  }
+  return out;
+}