Always forbid bids that add up to the cards in hand

The sum of all bids may never equal the number of cards each player
holds in the round; the last bidder has to adjust their bid. This was an
optional "not equal" lobby setting and is now a fixed rule of the game
engine, so it applies to humans, AI players and training alike.

- Remove GameOptions.not_equal, the set_options field, the lobby toggle
  and the --not-equal training flag
- Explain the rule in the lobby and show the blocked bid while bidding
- Drop the option from the AI observation encoding
- Tests check that no round ends with bids summing to the cards in hand

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

wizard_website/src/api/types.ts

@@ -19,7 +19,6 @@ export type Action =
 export type Phase = 'trump_selection' | 'bidding' | 'playing' | 'finished'
 
 export interface GameOptions {
-  not_equal: boolean
   hidden_bids: boolean
 }
 
@@ -115,7 +114,7 @@ export type ClientMessage =
   | { type: 'leave_lobby' }
   | { type: 'add_ai' }
   | { type: 'remove_player'; player_id: string }
-  | { type: 'set_options'; not_equal: boolean; hidden_bids: boolean }
+  | { type: 'set_options'; hidden_bids: boolean }
   | { type: 'start_game' }
   | { type: 'action'; action: Action }
   | { type: 'return_to_lobby' }

wizard_website/src/screens/GameScreen/BidPanel.tsx

@@ -34,7 +34,7 @@ export function BidPanel({ observation, onBid }: BidPanelProps) {
       <p className={styles.hint}>
         {!observation.options.hidden_bids &&
           `Bids so far: ${sum} for ${observation.round_number} trick${observation.round_number > 1 ? 's' : ''}. `}
-        {forbidden.length > 0 && `Not-equal rule: you may not bid ${forbidden.join(', ')}.`}
+        {forbidden.length > 0 && `The bids may not add up to ${observation.round_number}, so you may not bid ${forbidden.join(', ')}.`}
       </p>
     </div>
   )

wizard_website/src/screens/LobbyScreen/LobbyScreen.module.css

@@ -205,3 +205,9 @@
   margin: 0;
   color: var(--text-muted);
 }
+
+.rule {
+  margin: 0 0 4px;
+  color: var(--text-muted);
+  font-size: 14px;
+}

wizard_website/src/screens/LobbyScreen/LobbyScreen.tsx

@@ -98,18 +98,10 @@ export function LobbyScreen({ lobby, playerId, actions }: LobbyScreenProps) {
 
       <section className={styles.card}>
         <h2 className={styles.heading}>Rules</h2>
-        <label className={styles.option}>
-          <input
-            type="checkbox"
-            checked={lobby.options.not_equal}
-            disabled={!isHost}
-            onChange={(event) => actions.setOptions({ ...lobby.options, not_equal: event.target.checked })}
-          />
-          <span>
-            <strong>Not equal</strong>
-            <small>The sum of all bids must not equal the number of tricks in the round.</small>
-          </span>
-        </label>
+        <p className={styles.rule}>
+          The sum of all bids may never equal the number of cards in hand — the last player to bid has
+          to adjust their bid.
+        </p>
         <label className={styles.option}>
           <input
             type="checkbox"