feat(phase-30): add coverage snapshots, temporal comparison and auto re-testing (T-230 to T-232)

backend/app/models/test.py

@@ -1,7 +1,7 @@
 import uuid
 from datetime import datetime
 
-from sqlalchemy import Column, String, Text, Boolean, DateTime, ForeignKey, Enum
+from sqlalchemy import Column, String, Text, Boolean, Integer, DateTime, ForeignKey, Enum
 from sqlalchemy.dialects.postgresql import UUID
 from sqlalchemy.orm import relationship
 
@@ -54,6 +54,10 @@ class Test(Base):
     remediation_status = Column(String, nullable=True)  # pending / in_progress / completed / not_applicable
     remediation_assignee = Column(UUID(as_uuid=True), ForeignKey("users.id"), nullable=True)
 
+    # ── Re-test fields ────────────────────────────────────────────
+    retest_of = Column(UUID(as_uuid=True), ForeignKey("tests.id"), nullable=True)
+    retest_count = Column(Integer, default=0)
+
     # ── Relationships ───────────────────────────────────────────────
     technique = relationship("Technique", back_populates="tests")
     evidences = relationship("Evidence", back_populates="test")
@@ -61,3 +65,5 @@ class Test(Base):
     red_validator = relationship("User", foreign_keys=[red_validated_by])
     blue_validator = relationship("User", foreign_keys=[blue_validated_by])
     remediation_user = relationship("User", foreign_keys=[remediation_assignee])
+    original_test = relationship("Test", remote_side="Test.id", foreign_keys=[retest_of])
+    retests = relationship("Test", foreign_keys=[retest_of], back_populates="original_test")