Prototype neutral Semuta reactions on clean ordinary discards

game/bot-semuta.ts

@@ -0,0 +1,28 @@
+import type { Action, GameView } from './engine';
+import { SEMUTA_DRUG_ID } from './semuta-drug';
+
+/** The offer is public, but only this seat's hand can justify committing. The
+ * fresh discard faces are never inspected until the private select stage. */
+export function botSemutaActions(g: GameView): Action[] {
+  const reaction = g.semutaReaction;
+  if (g.status !== 'playing' || !reaction?.event) return [];
+
+  if (reaction.stage === 'select') {
+    // Only the committed claimant receives candidates. A mandatory selection
+    // must still complete when no strategic preference is available.
+    const choice = reaction.candidates.find((card) => card.id);
+    return choice
+      ? [{ type: 'semutaSelect', event: reaction.event, card: choice.id }]
+      : [];
+  }
+
+  if (reaction.stage !== 'offer' || reaction.passed) return [];
+  const own = g.players.find((player) => player.id === g.me);
+  const hasSemuta = own?.hand?.some(
+    (card) => card.id === SEMUTA_DRUG_ID &&
+      card.kind === 'special' && card.effect === 'semutaDrug',
+  );
+  if (reaction.canCommit && !reaction.blocked && hasSemuta)
+    return [{ type: 'semutaCommit', event: reaction.event }];
+  return [{ type: 'semutaPass', event: reaction.event }];
+}