Add suggestPositionShot schema types and operation

Mirrors the backend's position-play search: SuggestPositionShotInputGQL
(pot lock + target-area polygon), PositionSuggestionGQL /
PositionShotCandidateGQL / CueStrikeGQL, the Query field, and a
SuggestPositionShot operation with a shared candidate fragment. Rebased
onto master's gql; index.tsx regenerated.

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

src/operations/shot_simulation.gql

@@ -85,3 +85,53 @@ query ComputePotAim(
     occludingBallIds
   }
 }
+
+fragment PositionShotCandidate on PositionShotCandidateGQL {
+  strike {
+    v0
+    phi
+    theta
+    a
+    b
+  }
+  cueFinalPosition
+  inTargetArea
+  distanceToTargetArea
+  robustness
+  potted
+  scratched
+  projection {
+    trajectories {
+      ballId
+      points {
+        time
+        position
+      }
+    }
+    events {
+      eventType
+      time
+      ballIds
+      position
+    }
+    finalState {
+      ballId
+      position
+    }
+    pottedBallIds
+  }
+}
+
+query SuggestPositionShot($suggestionInput: SuggestPositionShotInputGQL!) {
+  suggestPositionShot(suggestionInput: $suggestionInput) {
+    achievable
+    evaluatedCount
+    successfulCount
+    best {
+      ...PositionShotCandidate
+    }
+    alternates {
+      ...PositionShotCandidate
+    }
+  }
+}