feat(web): Multi-Copy modal earlier; Multi-Copy stage before lands; bump version to 2.1.1; update CHANGELOG\n\n- Modal triggers after commander selection (Step 2)\n- Multi-Copy applied first in Step 5, lands next\n- Keep mc_summary/clamp/adjustments wiring intact\n- Tests green

code/tests/test_multi_copy_detector.py

@@ -0,0 +1,36 @@
+from deck_builder import builder_utils as bu
+
+
+class DummyBuilder:
+    def __init__(self, color_identity, selected_tags=None, commander_dict=None):
+        self.color_identity = color_identity
+        self.selected_tags = selected_tags or []
+        self.commander_dict = commander_dict or {"Themes": []}
+
+
+def test_detector_dragon_approach_minimal():
+    b = DummyBuilder(color_identity=['R'], selected_tags=['Spellslinger'])
+    results = bu.detect_viable_multi_copy_archetypes(b)
+    ids = [r['id'] for r in results]
+    assert 'dragons_approach' in ids
+    da = next(r for r in results if r['id']=='dragons_approach')
+    assert da['name'] == "Dragon's Approach"
+    assert da['type_hint'] == 'noncreature'
+    assert da['default_count'] == 25
+
+
+def test_detector_exclusive_rats_only_one():
+    b = DummyBuilder(color_identity=['B'], selected_tags=['rats','aristocrats'])
+    results = bu.detect_viable_multi_copy_archetypes(b)
+    rat_ids = [r['id'] for r in results if r.get('exclusive_group')=='rats']
+    # Detector should keep only one rats archetype in the ranked output
+    assert len(rat_ids) == 1
+    assert rat_ids[0] in ('relentless_rats','rat_colony')
+
+
+def test_detector_color_gate_blocks():
+    b = DummyBuilder(color_identity=['G'], selected_tags=['Spellslinger'])
+    results = bu.detect_viable_multi_copy_archetypes(b)
+    ids = [r['id'] for r in results]
+    # DA is red, shouldn't appear in mono-G
+    assert 'dragons_approach' not in ids