Add protocol-certification M2 L0 structural certifier (2.66.0).

Presence and connection only. FAIL solely on missing MANDATORY structure.
AXI4 internal is NOT_APPLICABLE, not FAIL. RECOMMENDED never FAIL. No L1–L3
and no invented ohms/mm/ps.

tests/pcb/test_protocol_recognize_m1.py

@@ -13,7 +13,6 @@ from backend.periscopex.models import (
     PinConnection,
 )
 from backend.periscopex.protocol_recognize import (
-    PACK_MACROPHASE,
     protocol_section_for_graph,
     recognize_physical_buses,
 )
@@ -143,7 +142,6 @@ def test_empty_graph_keeps_nessun_protocollo():
     sec = protocol_section_for_graph(DesignGraph())
     assert sec.message == "nessun protocollo riconosciuto"
     assert sec.recognized_instances == []
-    assert sec.macrophase == PACK_MACROPHASE
     blob = json.dumps(sec.model_dump())
     assert "ohm" not in blob.lower()
 
@@ -151,7 +149,6 @@ def test_empty_graph_keeps_nessun_protocollo():
 def test_report_section_lists_usb_without_z():
     sec = protocol_section_for_graph(_usb_graph())
     assert sec.recognized_instances
-    assert sec.max_level_reached is None
     blob = json.dumps(sec.model_dump())
     assert "90" not in blob
     assert "Zdiff" not in blob