Around the Corner bends every spell, hairpins included

Two holes, found when a SAFE cast at a treasure 'around the 180 degree
corner' refused with no line of sight (room LZ5R). First: the bend was
honored only in the attack path — every neutral resolve (creations,
summons, utilities, edge targets) checked straight sight and ignored
the attached card, though the card says 'any line of sight spell'.
castSight/castSightEdge now thread the bend through all of them, and
the chronicle narrates the neutral bend too.

Second: the bend itself pivoted only at cell centers, so the card's
flagship shot — doubling back up to 180 degrees around a wall's end —
never resolved: both legs graze the corner and die. The pivot may now
sit in the wall's open gap itself (bentSightThroughGap), which is what
rounding a corner physically is. Closed doors still block; two corners
still refuse.

The client lights bent-reachable squares for real now instead of the
old one-step-adjacency guess, creations included. Pure widening, so no
rev bump: every one of these casts was refused before, so no ledger
holds one. All 26 production ledgers replay clean; the LZ5R moment
itself replayed and the exact refused cast now lands.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015RCWSTnb1KYTPyL4GmhGnF

packages/engine/src/view.ts

@@ -2,7 +2,7 @@
 // The server sends this after every state change; clients never see the
 // deck order or other players' hands.
 
-import { SIDES, edgeKey, sightBetween, traceSight, type AssembledBoard, type Cell, type SightTrace } from "./board";
+import { SIDES, edgeKey, sightBetween, bentSightThroughGap, traceSight, type AssembledBoard, type Cell, type SightTrace } from "./board";
 import { cardDef, type CardInstance } from "./cards";
 import {
   boardView,
@@ -223,6 +223,32 @@ export function sightedCellsFor(view: GameView): Set<string> {
   return out;
 }
 
+/**
+ * Sight with an AROUND THE CORNER attached: every square straightly sighted,
+ * plus every square visible from one of those — the caster looks to a middle
+ * cell and the spell turns there, mirroring the engine's bentLos.
+ */
+export function bentSightedCellsFor(view: GameView): Set<string> {
+  const out = sightedCellsFor(view);
+  const me = view.players.find((p) => p.id === view.you);
+  if (!me) return out;
+  const mids = [...out].map((k) => {
+    const [x, y] = k.split(",").map(Number) as [number, number];
+    return { x, y };
+  });
+  const { board, blockers } = sightBasis(view);
+  for (const key of Object.keys(board.cells)) {
+    if (out.has(key)) continue;
+    const [x, y] = key.split(",").map(Number) as [number, number];
+    const cell = { x, y };
+    if (mids.some((mid) => sightBetween(board, mid, cell, blockers)) ||
+        bentSightThroughGap(board, me.position, cell, blockers)) {
+      out.add(key);
+    }
+  }
+  return out;
+}
+
 /** The board-as-seen and sight blockers this view's sight rules run against. */
 function sightBasis(view: GameView): { board: GameView["board"]; blockers: Record<string, true> } {
   // Held-open doors are open doorways to every eye. Beyond them, the
@@ -337,12 +363,12 @@ const SUMMON_CARD_IDS = new Set([
  * aid — mirroring the engine's own validation from the viewer's knowledge.
  * Null = this card's eligibility is not modeled; light everything.
  */
-export function eligibleCellsFor(view: GameView, cardId: string): Set<string> | null {
+export function eligibleCellsFor(view: GameView, cardId: string, bentCorner = false): Set<string> | null {
   const me = view.players.find((p) => p.id === view.you);
   if (!me) return null;
   const cells = Object.keys(view.board.cells);
   const key = (x: number, y: number) => `${x},${y}`;
-  const sighted = sightedCellsFor(view);
+  const sighted = bentCorner ? bentSightedCellsFor(view) : sightedCellsFor(view);
 
   if (CREATION_CARD_IDS.has(cardId)) {
     // emptySquareTarget: on the board, unoccupied by content, home, wizard,