fix: resolve all 64 mypy errors across backend

- Add dict[str, Any] / list[Any] type params throughout (fingerprint, models, schemas, scanner, status_checker)
- Add return type annotations to all route functions (nodes, edges, canvas, scan, auth, status, main)
- Fix no-any-return in security.py: cast pwd/jwt results to bool/str explicitly
- Fix canvas.py: use model_validate() for NodeResponse/EdgeResponse, rename db_node/db_edge upsert vars
- Fix scheduler.py: rename 'result' → 'check_result' to avoid type collision
- Fix get_db() return type: AsyncGenerator[AsyncSession, None]
- Add types-PyYAML for yaml import stubs
- Fix scanner.py: remove unnecessary type: ignore comment (nmap has stubs)
- Fix scan.py: wrap scalars().all() with list() for Sequence→list compatibility

backend/app/api/routes/canvas.py

@@ -1,4 +1,5 @@
 from datetime import UTC, datetime
+from typing import Any
 
 from fastapi import APIRouter, Depends
 from sqlalchemy import select
@@ -8,21 +9,29 @@ from app.api.deps import get_current_user
 from app.db.database import get_db
 from app.db.models import CanvasState, Edge, Node
 from app.schemas.canvas import CanvasSaveRequest, CanvasStateResponse
+from app.schemas.edges import EdgeResponse
+from app.schemas.nodes import NodeResponse
 
 router = APIRouter()
 
 
 @router.get("", response_model=CanvasStateResponse)
-async def load_canvas(db: AsyncSession = Depends(get_db), _: str = Depends(get_current_user)):
+async def load_canvas(db: AsyncSession = Depends(get_db), _: str = Depends(get_current_user)) -> CanvasStateResponse:
     nodes = (await db.execute(select(Node))).scalars().all()
     edges = (await db.execute(select(Edge))).scalars().all()
     state = await db.get(CanvasState, 1)
-    viewport = state.viewport if state else {"x": 0, "y": 0, "zoom": 1}
-    return CanvasStateResponse(nodes=list(nodes), edges=list(edges), viewport=viewport)
+    viewport: dict[str, Any] = state.viewport if state else {"x": 0, "y": 0, "zoom": 1}
+    return CanvasStateResponse(
+        nodes=[NodeResponse.model_validate(n) for n in nodes],
+        edges=[EdgeResponse.model_validate(e) for e in edges],
+        viewport=viewport,
+    )
 
 
 @router.post("/save")
-async def save_canvas(body: CanvasSaveRequest, db: AsyncSession = Depends(get_db), _: str = Depends(get_current_user)):
+async def save_canvas(
+    body: CanvasSaveRequest, db: AsyncSession = Depends(get_db), _: str = Depends(get_current_user)
+) -> dict[str, bool]:
     incoming_node_ids = {n.id for n in body.nodes}
     incoming_edge_ids = {e.id for e in body.edges}
 
@@ -42,19 +51,19 @@ async def save_canvas(body: CanvasSaveRequest, db: AsyncSession = Depends(get_db
 
     # Upsert nodes
     for node_data in body.nodes:
-        node = await db.get(Node, node_data.id)
-        if node:
+        db_node = await db.get(Node, node_data.id)
+        if db_node:
             for field, value in node_data.model_dump().items():
-                setattr(node, field, value)
+                setattr(db_node, field, value)
         else:
             db.add(Node(**node_data.model_dump()))
 
     # Upsert edges
     for edge_data in body.edges:
-        edge = await db.get(Edge, edge_data.id)
-        if edge:
+        db_edge = await db.get(Edge, edge_data.id)
+        if db_edge:
             for field, value in edge_data.model_dump().items():
-                setattr(edge, field, value)
+                setattr(db_edge, field, value)
         else:
             db.add(Edge(**edge_data.model_dump()))