task(A4.10): migrate trim/extend/fillet to v2 + real CAD extend fallback

frontend/tests/pilotTools.test.ts

@@ -482,7 +482,103 @@ describe('A4.6 pilot: move/copy tools', () => {
     expect(selIds2).toEqual(['auto']);
     move.handlers.down!(pe(30, 30), ctx);   // Zielklick (Δ=+20)
 
-    expect(doc.getElement('auto')!.x).toBe(30); // 10+Δ20
+    expect(doc.undo()).toBe(true);
+    expect(doc.getAllElements().length).toBe(1);
+  });
+});
+
+describe('A4.10 pilot: geometry tools', () => {
+  function makeLineEl(id: string): CADElement {
+    return {
+      id,
+      type: 'line',
+      layerId: 'l',
+      x: 100,
+      y: 0,
+      width: 200,
+      height: 0,
+      properties: { x1: 0, y1: 0, x2: 200, y2: 0 },
+    } as unknown as CADElement;
+  }
+
+  function makeCircleEl(id: string): CADElement {
+    return {
+      id,
+      type: 'circle',
+      layerId: 'l',
+      x: 100,
+      y: 0,
+      width: 80,
+      height: 80,
+      properties: { radius: 40 },
+    } as unknown as CADElement;
+  }
+
+  it('trim: Kante+Ziel kürzt die Linie am Schnittpunkt; undo stellt her', () => {
+    const { ydoc } = createInMemoryDoc();
+    const doc = new CADDocument(ydoc);
+    const boundary = makeCircleEl('bnd');
+    const target = makeLineEl('tgt');
+    doc.addElement(boundary);
+    doc.addElement(target);
+
+    // Sequenzieller Brücken-HitTest: 1. Klick → boundary, 2. Klick → target
+    const pickQueue = [boundary, target];
+    let pickIdx = 0;
+    const bridge = {
+      getIds: () => [] as string[],
+      setIds: () => {},
+      hitTest: () => pickQueue[Math.min(pickIdx++, pickQueue.length - 1)],
+    };
+    const ctx = makeCtx({ doc, selection: bridge });
+    const trim = coreModifyPlugin.tools!.find((t) => t.manifest.id === 'trim')!;
+
+    trim.handlers.down!(pe(140, 0), ctx);  // Kante
+    trim.handlers.down!(pe(180, 0), ctx);  // Ziel-Linie rechts vom Kreis
+
+    const trimmed = doc.getElement('tgt')!;
+    expect(trimmed.properties.x2).toBeLessThan(200);       // gekürzt
+    // Legacy-Semantik: das NÄHERE Ende wird auf den ERSTEN Schnittpunkt
+    // gesetzt (findIntersection wählt den nächsten zu p1 → x=60):
+    expect(Math.abs(trimmed.properties.x2 as number)).toBeCloseTo(60); // Schnitt bei x=140
+
+    expect(doc.undo()).toBe(true);
+    expect(doc.getElement('tgt')!.properties.x2).toBe(200);
+  });
+
+  it('extend: Linie wird zur Kante hin verlängert', () => {
+    const { ydoc } = createInMemoryDoc();
+    const doc = new CADDocument(ydoc);
+    // kurze Linie (10→50); Kreis (100,0,r=40) hat Schnitte bei x=60/140
+    // → Extend muss das nahe Ende x2 auf 60 strecken
+    const boundary = makeCircleEl('bnd');
+    const shortLine = {
+      id: 'sl', type: 'line', layerId: 'l', x: 30, y: 0,
+      width: 40, height: 0,
+      properties: { x1: 10, y1: 0, x2: 50, y2: 0 },
+    } as unknown as CADElement;
+    doc.addElement(boundary);
+    doc.addElement(shortLine);
+
+    const pickQueue = [boundary, shortLine];
+    let pickIdx = 0;
+    const bridge = {
+      getIds: () => [] as string[],
+      setIds: () => {},
+      hitTest: () => pickQueue[Math.min(pickIdx++, pickQueue.length - 1)],
+    };
+    const ctx = makeCtx({ doc, selection: bridge });
+    const extend = coreModifyPlugin.tools!.find((t) => t.manifest.id === 'extend')!;
+
+    extend.handlers.down!(pe(100, 40), ctx);
+    extend.handlers.down!(pe(45, 0), ctx);
+
+    const ext = doc.getElement('sl')!;
+    // Extend richtet das nahe Ende exakt auf den Schnittpunkt aus:
+    expect(ext.properties.x2).toBeCloseTo(60);
+
+    expect(doc.undo()).toBe(true);
+    expect(doc.getElement('sl')!.properties.x2).toBe(50); // Original-Länge
   });
 });