Fix place_cups success condition to accept any N distinct cups

[llm-learner]

Problem

The instruction says "place 1 cup on the cup holder", without specifying which cup. However, _on_peg_conditions[:index + 1] requires mug0 for variation 0 and mug0 + mug1 for variation 1.

In place_cups/variation0/episodes/episode2 (all_variations/episodes/episode13), mug2 is placed on the holder and released. The sensor detects it, the gripper is empty, but the original success condition remains false for 200 physics steps (~10 seconds).

The video uses the PerAct fork and CoppeliaSim 4.1.0, with the original success condition. The same predicate is present in upstream 02720bba; a full-scene integration test against current upstream has not been run.

Fix

Check any N distinct cups using the existing ConditionSet and OrConditions. Keep the current sensors and NothingGrasped requirement. Multiple sensors detecting one cup still count as one cup. Variation 2 is unchanged.

Test

The regression test covers all 3 variations, 512 cup/sensor detection matrices, and both gripper states: 3,072 checks. The original predicate fails 161 checks; the corrected predicate passes all checks. These are mocked-sensor unit tests.

中文说明

指令只要求杯子数量，没有指定编号，但原判据要求固定的前 N 个杯子。视频中放好的是 mug2：传感器检测到它、夹爪已松开，但原环境仍判失败。视频来自 PerAct 环境；上游源码存在相同判据，尚未进行当前上游完整场景的集成测试。

修复改为检查任意 N 个不同杯子，保留原传感器和夹爪为空条件，不重复计数同一杯子。回归测试覆盖3,072种状态，原判据161项失败，修正后全部通过。该修改会影响 variation 0/1 的成功率统计，评测时应注明所用版本。

place_cups_test20_original_bug_zh_en.mp4

PerAct counterpart: MohitShridhar#3