fix(puzzle): an object steps once per movement phase; negated conversion is settled per object

Bug 1 (modules 08-10): a YOU object pulled by an earlier mover took a second step of its own. Level movement now keeps the ids that stepped in a committed plan this phase; such a YOU object starts no move, and Planner try_move answers no for it. Regression: test_08x_pulled_you_moves_once (Module 8 Expansion Drop).

Bug 2 (modules 09-10): convert honoured negation only per rule, so ALL IS ROCK beat BABA IS NOT ROCK. A target Y is now skipped for an object if any active negated rule IS NOT Y names it. Module 9 and 10 references (and their drop solutions) now carry ALL, the Module 7 Expansion Drop. Regression: test_09_negated_conversion_beats_group.

Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>

course/09-turn-pipeline/reference/ts/src/engine/puzzle/level.ts

@@ -141,6 +141,10 @@ export class Level {
    * The `YOU` objects move one at a time, the one furthest ahead in `dir` first
    * (oldest first on a tie); each one's move is planned in full, then committed,
    * before the next is planned. Every move uses the rules in force before the first.
+   *
+   * An object steps at most once in a movement phase. A `YOU` object that an
+   * earlier move already carried along (pushed, or moved by any other response)
+   * doesn't start a move of its own, and no later move can make it step again.
    */
   private movement(dir: Dir): void {
     const [dx, dy] = delta(dir);
@@ -150,10 +154,15 @@ export class Level {
       .filter((o) => this.hasProperty(o.id, YOU))
       .sort((a, b) => ahead(b) - ahead(a) || a.id - b.id)
       .map((o) => o.id);
+    const stepped = new Set<ObjectId>();
     for (const id of you) {
       if (this.board.find(id) === undefined) continue; // destroyed by an earlier move
-      const planner = new Planner(this, dir);
-      if (planner.tryMove(id)) this.commit(planner.result(), dir);
+      if (stepped.has(id)) continue; // already moved, by an earlier move
+      const planner = new Planner(this, dir, stepped);
+      if (!planner.tryMove(id)) continue;
+      const plan = planner.result();
+      this.commit(plan, dir);
+      for (const moved of plan.moving) if (!plan.destroyed.has(moved)) stepped.add(moved);
     }
   }
 
@@ -169,6 +178,10 @@ export class Level {
    * this. An object named by `X IS NOT X` is deleted, and still makes its `Y`s,
    * as new objects: the negation cancelled `X IS X`.
    *
+   * Negation is settled per object, as in `hasProperty`: an object doesn't become
+   * a `Y` if any active `... IS NOT Y` names it, whatever noun gave it the
+   * conversion (`ALL IS Y` with `X IS NOT Y` leaves every X an X).
+   *
    * Every object is decided from the board as movement left it, before any
    * changes, so `X IS Y` and `Y IS X` swap the Xs and the Ys.
    */
@@ -182,6 +195,7 @@ export class Level {
       if (!locked) {
         for (const r of aboutIt) {
           if (r.negated || !isConversion(r)) continue;
+          if (aboutIt.some((n) => n.negated && n.complement === r.complement)) continue;
           const kind = this.lexicon.thingNamed(r.complement);
           if (kind === undefined) continue;
           const same = (k: Kind) => Kind.format(k) === Kind.format(kind);