feat(tests): add Blue detect_procedure field mapped from template suggestion

Blue Team gets a detect_procedure field on Test (what they actually
did to detect the attack), Blue's counterpart to Red's procedure_text.
It's seeded from a new detect_suggested_procedure field on
TestTemplate at test-creation time, so a junior who later reuses the
same template starts with prior guidance instead of a blank field.

Also adds the procedure_suggestions review table and Test.source_template_id,
laying the groundwork for suggesting template improvements from filled-in
procedure fields (reviewed and approved by a lead, never auto-written).
detect_procedure is archived (not cleared) on Blue reopen, matching
blue_summary, and now appears in the Jira round-archived and blue_review
comments alongside the existing detection/containment fields.

backend/app/models/procedure_suggestion.py

@@ -0,0 +1,41 @@
+"""SQLAlchemy model for procedure-improvement suggestions.
+
+When an operator submits a round with a filled-in procedure field
+(``procedure_text`` for Red, ``detect_procedure`` for Blue), the command(s)
+in it are extracted heuristically and proposed as an update to the
+originating template's suggested-procedure field. Nothing is written to
+the template automatically — a lead reviews and approves or rejects each
+suggestion, so a junior who later picks up the same template only ever
+sees vetted guidance.
+"""
+
+import uuid
+
+from sqlalchemy import Column, DateTime, ForeignKey, String, Text, func
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import relationship
+
+from app.database import Base
+
+
+class ProcedureSuggestion(Base):
+    """A proposed update to a TestTemplate's suggested procedure, pending lead review."""
+
+    __tablename__ = "procedure_suggestions"
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    template_id = Column(UUID(as_uuid=True), ForeignKey("test_templates.id"), nullable=False)
+    team = Column(String(10), nullable=False)  # "red" or "blue"
+    suggested_text = Column(Text, nullable=False)
+    source_test_id = Column(UUID(as_uuid=True), ForeignKey("tests.id"), nullable=True)
+    submitted_by = Column(UUID(as_uuid=True), ForeignKey("users.id"), nullable=True)
+
+    status = Column(String(10), nullable=False, default="pending", server_default="pending")  # pending/approved/rejected
+    reviewed_by = Column(UUID(as_uuid=True), ForeignKey("users.id"), nullable=True)
+    reviewed_at = Column(DateTime, nullable=True)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+
+    template = relationship("TestTemplate", foreign_keys=[template_id])
+    source_test = relationship("Test", foreign_keys=[source_test_id])
+    submitter = relationship("User", foreign_keys=[submitted_by])
+    reviewer = relationship("User", foreign_keys=[reviewed_by])