Split cart into 4 microservices: relations, likes, orders, page-config→blog

Phase 1 - Relations service (internal): owns ContainerRelation, exposes
get-children data + attach/detach-child actions. Retargeted events, blog,
market callers from cart to relations.

Phase 2 - Likes service (internal): unified Like model replaces ProductLike
and PostLike with generic target_type/target_slug/target_id. Exposes
is-liked, liked-slugs, liked-ids data + toggle action.

Phase 3 - PageConfig → blog: moved ownership to blog with direct DB queries,
removed proxy endpoints from cart.

Phase 4 - Orders service (public): owns Order/OrderItem + SumUp checkout
flow. Cart checkout now delegates to orders via create-order action.
Webhook/return routes and reconciliation moved to orders.

Phase 5 - Infrastructure: docker-compose, deploy.sh, Dockerfiles updated
for all 3 new services. Added orders_url helper and factory model imports.

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

shared/models/ghost_content.py

@@ -131,12 +131,6 @@ class Post(Base):
         back_populates="posts",
         order_by="PostTag.sort_order",
     )
-    likes: Mapped[List["PostLike"]] = relationship(
-        "PostLike",
-        back_populates="post",
-        cascade="all, delete-orphan",
-        passive_deletes=True,
-    )
 
 class Author(Base):
     __tablename__ = "authors"
@@ -198,15 +192,3 @@ class PostTag(Base):
     sort_order: Mapped[int] = mapped_column(Integer, default=0, nullable=False)
 
 
-class PostLike(Base):
-    __tablename__ = "post_likes"
-
-    id = Column(Integer, primary_key=True, autoincrement=True)
-    user_id = Column(Integer, nullable=False)
-    post_id: Mapped[int] = mapped_column(ForeignKey("posts.id", ondelete="CASCADE"), nullable=False)
-
-    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
-    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
-    deleted_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True))
-
-    post: Mapped["Post"] = relationship("Post", back_populates="likes", foreign_keys=[post_id])