PAct Min-Evidence Ablation

只改变输入 mask 中隐藏/微小 part 的 minimum evidence area，PAct sampler 保持官方默认 25/25，不传 CFG/step override，不做 VLM 分析。

span1_cardinalityscore 45.83part MAE 1.20joint F1 0.146

span2_min_evidencescore 50.81part MAE 1.00joint F1 0.259

span3_overexpandedscore 43.52part MAE 1.20joint F1 0.086

GT parts: 7 · movable: 6

run	score	joint F1
span1_cardinality	48.98	0.200
span2_min_evidence	55.87	0.364
span3_overexpanded	40.54	0.000

GT parts: 12 · movable: 11

run	score	part MAE	joint F1
span1_cardinality	51.77	3	0.333
span2_min_evidence	68.78	3	0.737
span3_overexpanded	48.38	2	0.211

GT parts: 21 · movable: 20

run	score	part MAE	joint F1
span1_cardinality	45.62	2	0.118
span2_min_evidence	46.52	1	0.114
span3_overexpanded	45.16	2	0.108

GT parts: 31 · movable: 30

run	score	part MAE	joint F1
span1_cardinality	44.30	0	0.077
span2_min_evidence	44.41	0	0.080
span3_overexpanded	45.07	1	0.111

GT parts: 6 · movable: 5

run	score	part MAE
span1_cardinality	38.46	1
span2_min_evidence	38.46	1
span3_overexpanded	38.45	1