Phase 5: Remove cross-domain FKs and relationships from calendar models

- CalendarEntry.order_id: plain Integer column (no FK to orders)
- CalendarEntry: remove order relationship
- Ticket.order_id: plain Integer column (no FK to orders)
- Ticket: remove order relationship

Cross-domain bridging now handled by glue services.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

models/calendars.py

@@ -80,7 +80,7 @@ class CalendarEntry(Base):
     # NEW: ownership + order link
     user_id = Column(Integer, ForeignKey("users.id"), nullable=True, index=True)
     session_id = Column(String(64), nullable=True, index=True)
-    order_id = Column(Integer, ForeignKey("orders.id", ondelete="SET NULL"), nullable=True, index=True)
+    order_id = Column(Integer, nullable=True, index=True)
 
     # NEW: slot link
     slot_id = Column(Integer, ForeignKey("calendar_slots.id", ondelete="SET NULL"), nullable=True, index=True)
@@ -122,8 +122,6 @@ class CalendarEntry(Base):
 
     calendar = relationship("Calendar", back_populates="entries")
     slot = relationship("CalendarSlot", back_populates="entries", lazy="selectin")
-    # Optional, but handy:
-    order = relationship("Order", back_populates="calendar_entries", lazy="selectin")
     posts = relationship("CalendarEntryPost", back_populates="entry", cascade="all, delete-orphan")
     ticket_types = relationship(
         "TicketType",
@@ -249,12 +247,7 @@ class Ticket(Base):
     )
     user_id = Column(Integer, ForeignKey("users.id"), nullable=True, index=True)
     session_id = Column(String(64), nullable=True, index=True)
-    order_id = Column(
-        Integer,
-        ForeignKey("orders.id", ondelete="SET NULL"),
-        nullable=True,
-        index=True,
-    )
+    order_id = Column(Integer, nullable=True, index=True)
 
     code = Column(String(64), unique=True, nullable=False)  # QR/barcode value
     state = Column(
@@ -278,7 +271,6 @@ class Ticket(Base):
 
     entry = relationship("CalendarEntry", backref="tickets")
     ticket_type = relationship("TicketType", backref="tickets")
-    order = relationship("Order", backref="tickets")
 
 
 class CalendarEntryPost(Base):