Domain isolation: replace cross-domain imports with service calls

Replace direct Calendar, MarketPlace, and Post model queries with typed
service calls (services.blog, services.calendar, services.market,
services.cart). Blog registers all 4 services via domain_services_fn
with has() guards for composable deployment.

Key changes:
- app.py: use domain_services_fn instead of inline service registration
- admin routes: MarketPlace queries → services.market.marketplaces_for_container()
- entry_associations: CalendarEntryPost → services.calendar.entry_ids_for_content()
- markets service: Post query → services.blog.get_post_by_id/slug()
- posts_data, post routes: use calendar/market/cart services
- menu_items: glue imports → shared imports

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

bp/post/admin/routes.py

@@ -82,7 +82,7 @@ def register():
         pc = PageConfig(container_type="page", container_id=post_id, features={})
         g.s.add(pc)
         await g.s.flush()
-        from glue.services.relationships import attach_child
+        from shared.services.relationships import attach_child
         await attach_child(g.s, "page", post_id, "page_config", pc.id)
 
     # Parse request body
@@ -146,7 +146,7 @@ def register():
         pc = PageConfig(container_type="page", container_id=post_id, features={})
         g.s.add(pc)
         await g.s.flush()
-        from glue.services.relationships import attach_child
+        from shared.services.relationships import attach_child
         await attach_child(g.s, "page", post_id, "page_config", pc.id)
 
     form = await request.form
@@ -603,21 +603,14 @@ def register():
   @require_admin
   async def markets(slug: str):
     """List markets for this page."""
-    from shared.models.market_place import MarketPlace
-    from sqlalchemy import select as sa_select
+    from shared.services.registry import services
 
     post = (g.post_data or {}).get("post", {})
     post_id = post.get("id")
     if not post_id:
         return await make_response("Post not found", 404)
 
-    page_markets = (await g.s.execute(
-        sa_select(MarketPlace).where(
-            MarketPlace.container_type == "page",
-            MarketPlace.container_id == post_id,
-            MarketPlace.deleted_at.is_(None),
-        ).order_by(MarketPlace.name)
-    )).scalars().all()
+    page_markets = await services.market.marketplaces_for_container(g.s, "page", post_id)
 
     html = await render_template(
         "_types/post/admin/_markets_panel.html",
@@ -631,8 +624,7 @@ def register():
   async def create_market(slug: str):
     """Create a new market for this page."""
     from ..services.markets import create_market as _create_market, MarketError
-    from shared.models.market_place import MarketPlace
-    from sqlalchemy import select as sa_select
+    from shared.services.registry import services
     from quart import jsonify
 
     post = (g.post_data or {}).get("post", {})
@@ -649,13 +641,7 @@ def register():
         return jsonify({"error": str(e)}), 400
 
     # Return updated markets list
-    page_markets = (await g.s.execute(
-        sa_select(MarketPlace).where(
-            MarketPlace.container_type == "page",
-            MarketPlace.container_id == post_id,
-            MarketPlace.deleted_at.is_(None),
-        ).order_by(MarketPlace.name)
-    )).scalars().all()
+    page_markets = await services.market.marketplaces_for_container(g.s, "page", post_id)
 
     html = await render_template(
         "_types/post/admin/_markets_panel.html",
@@ -669,8 +655,7 @@ def register():
   async def delete_market(slug: str, market_slug: str):
     """Soft-delete a market."""
     from ..services.markets import soft_delete_market
-    from shared.models.market_place import MarketPlace
-    from sqlalchemy import select as sa_select
+    from shared.services.registry import services
     from quart import jsonify
 
     post = (g.post_data or {}).get("post", {})
@@ -681,13 +666,7 @@ def register():
         return jsonify({"error": "Market not found"}), 404
 
     # Return updated markets list
-    page_markets = (await g.s.execute(
-        sa_select(MarketPlace).where(
-            MarketPlace.container_type == "page",
-            MarketPlace.container_id == post_id,
-            MarketPlace.deleted_at.is_(None),
-        ).order_by(MarketPlace.name)
-    )).scalars().all()
+    page_markets = await services.market.marketplaces_for_container(g.s, "page", post_id)
 
     html = await render_template(
         "_types/post/admin/_markets_panel.html",