The first square of a two-square spell now shows on the board

Dimensional Warp, Trader, Redirection, and Relocate Sector all take
two clicks, but only the hint bar acknowledged the first — the board
itself sat unchanged until the second click landed. The first chosen
square now wears a pulsing amber dashed ring (same rhythm as the warp
destination ring, still under prefers-reduced-motion) until the spell
completes or is cancelled.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/web/src/App.svelte

@@ -760,6 +760,7 @@
           onPlayerClick={clickPlayer}
           onCreatureClick={clickCreature}
           onWarpClick={clickWarp}
+          markedCell={tradeFrom ?? pendingSectorFrom}
         />
       </section>