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/schemas.py

@@ -146,6 +146,44 @@ class DiagramFull(DiagramSummary):
     wire_bundles: List[WireBundleOut] = []
 
 
+# ── DiagramView ───────────────────────────────────────────────────────────────
+
+class DiagramViewBase(BaseModel):
+    name: str
+    route_mode: str = "direct"
+
+
+class DiagramViewCreate(DiagramViewBase):
+    diagram_id: int
+
+
+class DiagramViewUpdate(BaseModel):
+    name: Optional[str] = None
+    route_mode: Optional[str] = None
+
+
+class DiagramViewOut(DiagramViewBase):
+    id: int
+    diagram_id: int
+    created_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class ViewDevicePositionUpdate(BaseModel):
+    x: float
+    y: float
+
+
+class ViewWireWaypointsUpdate(BaseModel):
+    waypoints: List[Dict[str, Any]] = []
+
+
+class ViewLayout(BaseModel):
+    device_positions: Dict[int, Dict[str, float]] = {}
+    wire_waypoints: Dict[int, List[Dict[str, Any]]] = {}
+
+
 # ── CustomConnector ───────────────────────────────────────────────────────────
 
 class CustomConnectorBase(BaseModel):