STANEK: FIX #3669 Clearing stanek grid using API could crash the page.

Fix #3669 - Query the "activegrid" at each re-rerendering of the Stanek Page. Rather than using React useState and passing it as Props.

Tested with :
ns.clearLog()
ns.tail()
await ns.sleep(2000)

ns.print("Clearing gift")
await ns.sleep(1000);
ns.stanek.clearGift()

src/CotMG/ui/MainBoard.tsx

@@ -18,7 +18,6 @@ interface IProps {
 }
 
 export function MainBoard(props: IProps): React.ReactElement {
-  const [grid, setGrid] = React.useState(calculateGrid(props.gift));
   const [ghostGrid, setGhostGrid] = React.useState(zeros([props.gift.width(), props.gift.height()]));
   const [pos, setPos] = React.useState([0, 0]);
   const [rotation, setRotation] = React.useState(0);
@@ -54,12 +53,10 @@ export function MainBoard(props: IProps): React.ReactElement {
       if (!props.gift.canPlace(worldX, worldY, rotation, selectedFragment)) return;
       props.gift.place(worldX, worldY, rotation, selectedFragment);
     }
-    setGrid(calculateGrid(props.gift));
   }
 
   function clear(): void {
     props.gift.clear();
-    setGrid(zeros([props.gift.width(), props.gift.height()]));
   }
 
   function updateSelectedFragment(fragment: Fragment): void {
@@ -92,7 +89,6 @@ export function MainBoard(props: IProps): React.ReactElement {
           <Grid
             width={props.gift.width()}
             height={props.gift.height()}
-            activeGrid={grid}
             ghostGrid={ghostGrid}
             gift={props.gift}
             enter={(i, j) => moveGhost(i, j, rotation)}