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/assignment.py

@@ -18,8 +18,12 @@ class Assignment(Base):
 
     id: Mapped[int] = mapped_column(primary_key=True)
     participant_id: Mapped[int] = mapped_column(ForeignKey("participants.id", ondelete="CASCADE"), index=True)
-    challenge_id: Mapped[int] = mapped_column(ForeignKey("challenges.id", ondelete="CASCADE"))
+    challenge_id: Mapped[int | None] = mapped_column(ForeignKey("challenges.id", ondelete="CASCADE"), nullable=True)  # None для playthrough
     status: Mapped[str] = mapped_column(String(20), default=AssignmentStatus.ACTIVE.value)
+
+    # Для прохождений (playthrough)
+    game_id: Mapped[int | None] = mapped_column(ForeignKey("games.id", ondelete="CASCADE"), nullable=True, index=True)
+    is_playthrough: Mapped[bool] = mapped_column(Boolean, default=False)
     event_type: Mapped[str | None] = mapped_column(String(30), nullable=True)  # Event type when assignment was created
     is_event_assignment: Mapped[bool] = mapped_column(Boolean, default=False, index=True)  # True for Common Enemy assignments
     event_id: Mapped[int | None] = mapped_column(ForeignKey("events.id", ondelete="SET NULL"), nullable=True, index=True)  # Link to event
@@ -33,6 +37,8 @@ class Assignment(Base):
 
     # Relationships
     participant: Mapped["Participant"] = relationship("Participant", back_populates="assignments")
-    challenge: Mapped["Challenge"] = relationship("Challenge", back_populates="assignments")
+    challenge: Mapped["Challenge | None"] = relationship("Challenge", back_populates="assignments")
+    game: Mapped["Game | None"] = relationship("Game", back_populates="playthrough_assignments", foreign_keys=[game_id])
     event: Mapped["Event | None"] = relationship("Event", back_populates="assignments")
     dispute: Mapped["Dispute | None"] = relationship("Dispute", back_populates="assignment", uselist=False, cascade="all, delete-orphan", passive_deletes=True)
+    bonus_assignments: Mapped[list["BonusAssignment"]] = relationship("BonusAssignment", back_populates="main_assignment", cascade="all, delete-orphan")