Add views, import/duplicate, DRC, jumps toggle, multi-wire select, auto-route, delete view tabs

- Roadmap #22: File→Import JSON to restore a diagram (drag-drop or file picker)
- Roadmap #23: Duplicate diagram from diagram list
- Roadmap #24: DRC panel with collapsible categories (unconnected pins, dup refs, no length, no P/N)
- Multi-view tabs: named views per diagram with independent device/wire layouts; snapshot-on-entry prevents bleed
- Keyboard arrow nudge for selected device(s)
- Undo for move, duplicate, label/property changes
- Wire jump arcs toggle (⌒ Jumps button in toolbar)
- Shift+click multi-wire selection; right-click bulk clear waypoints or auto-route
- Auto-route: obstacle-avoiding ortho routing for single or bulk selected wires
- Delete view tab with × button; right-click context menu for rename/delete

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

backend/app/routers/diagrams.py

@@ -1,4 +1,4 @@
-from fastapi import APIRouter, Depends, HTTPException
+from fastapi import APIRouter, Depends, HTTPException, Request
 from sqlalchemy.orm import Session
 from typing import List
 from .. import models, schemas
@@ -51,3 +51,115 @@ def delete_diagram(diagram_id: int, db: Session = Depends(get_db)):
     db.delete(diagram)
     db.commit()
     return {"ok": True}
+
+
+@router.post("/{diagram_id}/duplicate", response_model=schemas.DiagramSummary, status_code=201)
+def duplicate_diagram(diagram_id: int, db: Session = Depends(get_db)):
+    src = db.query(models.Diagram).filter(models.Diagram.id == diagram_id).first()
+    if not src:
+        raise HTTPException(status_code=404, detail="Diagram not found")
+
+    new_diag = models.Diagram(name=f"{src.name} (copy)", description=src.description or "")
+    db.add(new_diag)
+    db.flush()
+
+    id_map = {}
+    for dev in src.devices:
+        new_dev = models.Device(
+            diagram_id=new_diag.id,
+            device_type=dev.device_type,
+            label=dev.label,
+            reference=dev.reference,
+            x=dev.x + 30,
+            y=dev.y + 30,
+            width=dev.width,
+            height=dev.height,
+            properties=dev.properties,
+            pins=dev.pins,
+        )
+        db.add(new_dev)
+        db.flush()
+        id_map[dev.id] = new_dev.id
+
+    for wire in src.wires:
+        new_wire = models.Wire(
+            diagram_id=new_diag.id,
+            label=wire.label,
+            from_device_id=id_map.get(wire.from_device_id),
+            from_pin=wire.from_pin,
+            to_device_id=id_map.get(wire.to_device_id),
+            to_pin=wire.to_pin,
+            color_primary=wire.color_primary,
+            color_stripe=wire.color_stripe,
+            gauge=wire.gauge,
+            length=wire.length,
+            length_unit=wire.length_unit,
+            notes=wire.notes or "",
+            waypoints=wire.waypoints or [],
+            twisted_pair=wire.twisted_pair,
+            twist_pitch=wire.twist_pitch,
+            shielded=wire.shielded,
+            show_size_label=wire.show_size_label,
+        )
+        db.add(new_wire)
+
+    db.commit()
+    db.refresh(new_diag)
+    return new_diag
+
+
+@router.post("/import", response_model=schemas.DiagramSummary, status_code=201)
+async def import_diagram(request: Request, db: Session = Depends(get_db)):
+    data = await request.json()
+
+    new_diag = models.Diagram(
+        name=data.get("name", "Imported Diagram"),
+        description=data.get("description", ""),
+    )
+    db.add(new_diag)
+    db.flush()
+
+    id_map = {}
+    for dev_data in data.get("devices", []):
+        new_dev = models.Device(
+            diagram_id=new_diag.id,
+            device_type=dev_data.get("device_type", "generic"),
+            label=dev_data.get("label", ""),
+            reference=dev_data.get("reference", ""),
+            x=dev_data.get("x", 100),
+            y=dev_data.get("y", 100),
+            width=dev_data.get("width", 120),
+            height=dev_data.get("height", 60),
+            properties=dev_data.get("properties", {}),
+            pins=dev_data.get("pins", []),
+        )
+        db.add(new_dev)
+        db.flush()
+        if "id" in dev_data:
+            id_map[dev_data["id"]] = new_dev.id
+
+    for wire_data in data.get("wires", []):
+        new_wire = models.Wire(
+            diagram_id=new_diag.id,
+            label=wire_data.get("label", ""),
+            from_device_id=id_map.get(wire_data.get("from_device_id")),
+            from_pin=wire_data.get("from_pin", ""),
+            to_device_id=id_map.get(wire_data.get("to_device_id")),
+            to_pin=wire_data.get("to_pin", ""),
+            color_primary=wire_data.get("color_primary", "#FF0000"),
+            color_stripe=wire_data.get("color_stripe"),
+            gauge=wire_data.get("gauge", "18 AWG"),
+            length=wire_data.get("length"),
+            length_unit=wire_data.get("length_unit", "in"),
+            notes=wire_data.get("notes", ""),
+            waypoints=wire_data.get("waypoints", []),
+            twisted_pair=wire_data.get("twisted_pair", False),
+            twist_pitch=wire_data.get("twist_pitch", 16.0),
+            shielded=wire_data.get("shielded", False),
+            show_size_label=wire_data.get("show_size_label", False),
+        )
+        db.add(new_wire)
+
+    db.commit()
+    db.refresh(new_diag)
+    return new_diag