Улучшение системы оспариваний и исправления

- Оспаривания теперь требуют решения админа после 24ч голосования
  - Можно повторно оспаривать после разрешённых споров
  - Исправлены бонусные очки при перепрохождении после оспаривания
  - Сброс серии при невалидном пруфе
  - Колесо показывает только доступные игры
  - Rate limiting только через backend (RATE_LIMIT_ENABLED)

backend/app/models/dispute.py

@@ -8,16 +8,19 @@ from app.core.database import Base
 
 class DisputeStatus(str, Enum):
     OPEN = "open"
+    PENDING_ADMIN = "pending_admin"  # Voting ended, waiting for admin decision
     RESOLVED_VALID = "valid"
     RESOLVED_INVALID = "invalid"
 
 
 class Dispute(Base):
-    """Dispute against a completed assignment's proof"""
+    """Dispute against a completed assignment's or bonus assignment's proof"""
     __tablename__ = "disputes"
 
     id: Mapped[int] = mapped_column(primary_key=True)
-    assignment_id: Mapped[int] = mapped_column(ForeignKey("assignments.id", ondelete="CASCADE"), unique=True, index=True)
+    # Either assignment_id OR bonus_assignment_id should be set (not both)
+    assignment_id: Mapped[int | None] = mapped_column(ForeignKey("assignments.id", ondelete="CASCADE"), nullable=True, index=True)
+    bonus_assignment_id: Mapped[int | None] = mapped_column(ForeignKey("bonus_assignments.id", ondelete="CASCADE"), nullable=True, index=True)
     raised_by_id: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"))
     reason: Mapped[str] = mapped_column(Text, nullable=False)
     status: Mapped[str] = mapped_column(String(20), default=DisputeStatus.OPEN.value)
@@ -26,6 +29,7 @@ class Dispute(Base):
 
     # Relationships
     assignment: Mapped["Assignment"] = relationship("Assignment", back_populates="dispute")
+    bonus_assignment: Mapped["BonusAssignment"] = relationship("BonusAssignment", back_populates="dispute")
     raised_by: Mapped["User"] = relationship("User", foreign_keys=[raised_by_id])
     comments: Mapped[list["DisputeComment"]] = relationship("DisputeComment", back_populates="dispute", cascade="all, delete-orphan")
     votes: Mapped[list["DisputeVote"]] = relationship("DisputeVote", back_populates="dispute", cascade="all, delete-orphan")