feat(hosting): signed preview URLs for POC sites

Replace the standalone POC viewer (duplicate rendering) with signed
JWT preview tokens that bypass StorefrontAccessMiddleware:

Architecture:
1. Admin clicks Preview → route generates signed JWT
2. Redirects to /storefront/{subdomain}/homepage?_preview=token
3. Middleware validates token signature + expiry + store_id
4. Sets request.state.is_preview = True, skips subscription check
5. Full storefront renders with HostWizard preview banner injected

New files:
- app/core/preview_token.py: create_preview_token/verify_preview_token

Changes:
- middleware/storefront_access.py: preview token bypass before sub check
- storefront/base.html: preview banner injection via is_preview state
- hosting/routes/pages/public.py: redirect with signed token (was direct render)
- hosting/routes/api/admin_sites.py: GET /sites/{id}/preview-url endpoint

Removed:
- hosting/templates/hosting/public/poc-viewer.html (replaced by storefront)

Benefits: one rendering path, all section types work, shareable 24h links.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/hosting/routes/api/admin_sites.py

@@ -44,6 +44,31 @@ def list_templates(
     )
 
 
+class PreviewUrlResponse(BaseModel):
+    """Response with signed preview URL."""
+
+    preview_url: str
+    expires_in_hours: int = 24
+
+
+@router.get("/sites/{site_id}/preview-url", response_model=PreviewUrlResponse)
+def get_preview_url(
+    site_id: int = Path(...),
+    db: Session = Depends(get_db),
+    current_admin: UserContext = Depends(get_current_admin_api),
+):
+    """Generate a signed preview URL for a hosted site."""
+    from app.core.preview_token import create_preview_token
+
+    site = hosted_site_service.get_by_id(db, site_id)
+    store = site.store
+    subdomain = store.subdomain or store.store_code
+    token = create_preview_token(store.id, subdomain, site.id)
+    return PreviewUrlResponse(
+        preview_url=f"/storefront/{subdomain}/?_preview={token}",
+    )
+
+
 class BuildPocRequest(BaseModel):
     """Request to build a POC site from prospect + template."""
 

app/modules/hosting/routes/pages/public.py

@@ -2,43 +2,40 @@
 """
 Hosting Public Page Routes.
 
-Public-facing routes for POC site viewing:
-- POC Viewer - Shows the Store's storefront with a HostWizard preview banner
+POC site preview via signed URL redirect to the storefront.
+The StorefrontAccessMiddleware validates the preview token and
+allows rendering without an active subscription.
 """
 
-from fastapi import APIRouter, Depends, Path, Request
-from fastapi.responses import HTMLResponse
+from fastapi import APIRouter, Depends, Path, Query
+from fastapi.responses import HTMLResponse, RedirectResponse
 from sqlalchemy.orm import Session
 
 from app.core.database import get_db
-from app.templates_config import templates
+from app.core.preview_token import create_preview_token
 
 router = APIRouter()
 
 
 @router.get(
     "/hosting/sites/{site_id}/preview",
-    response_class=HTMLResponse,
     include_in_schema=False,
 )
 async def poc_site_viewer(
-    request: Request,
     site_id: int = Path(..., description="Hosted Site ID"),
+    page: str = Query("homepage", description="Page slug to preview"),
     db: Session = Depends(get_db),
 ):
-    """Render POC site viewer with HostWizard preview banner.
+    """Redirect to storefront with signed preview token.
 
-    Renders CMS content directly (not via iframe to storefront) to
-    bypass the subscription access gate for pre-launch POC sites.
+    Generates a time-limited JWT and redirects to the store's
+    storefront URL. The StorefrontAccessMiddleware validates the
+    token and bypasses the subscription check.
     """
-    from app.modules.cms.models.content_page import ContentPage
-    from app.modules.cms.models.store_theme import StoreTheme
     from app.modules.hosting.models import HostedSite, HostedSiteStatus
-    from app.modules.tenancy.models import StorePlatform
 
     site = db.query(HostedSite).filter(HostedSite.id == site_id).first()
 
-    # Only allow viewing for poc_ready or proposal_sent sites
     if not site or site.status not in (
         HostedSiteStatus.POC_READY,
         HostedSiteStatus.PROPOSAL_SENT,
@@ -47,56 +44,31 @@ async def poc_site_viewer(
         return HTMLResponse(content="<h1>Site not available for preview</h1>", status_code=404)
 
     store = site.store
+    if not store:
+        return HTMLResponse(content="<h1>Store not found</h1>", status_code=404)
+
+    # Generate signed preview token — use subdomain for URL routing
+    subdomain = store.subdomain or store.store_code
+    token = create_preview_token(store.id, subdomain, site.id)
+
+    # Get platform code for dev-mode URL prefix
+    from app.core.config import settings
+    from app.modules.tenancy.models import StorePlatform
 
-    # Get platform_id for CMS query
     store_platform = (
         db.query(StorePlatform)
         .filter(StorePlatform.store_id == store.id)
         .first()
-    ) if store else None
-    platform_id = store_platform.platform_id if store_platform else None
-
-    # Load homepage (slug='homepage' from POC builder)
-    page = None
-    if platform_id:
-        page = (
-            db.query(ContentPage)
-            .filter(
-                ContentPage.platform_id == platform_id,
-                ContentPage.store_id == store.id,
-                ContentPage.slug == "homepage",
-                ContentPage.is_published.is_(True),
-            )
-            .first()
-        )
-
-    # Load all nav pages for this store
-    nav_pages = []
-    if platform_id:
-        nav_pages = (
-            db.query(ContentPage)
-            .filter(
-                ContentPage.platform_id == platform_id,
-                ContentPage.store_id == store.id,
-                ContentPage.is_published.is_(True),
-                ContentPage.show_in_header.is_(True),
-            )
-            .order_by(ContentPage.display_order)
-            .all()
-        )
-
-    # Load theme
-    theme = db.query(StoreTheme).filter(StoreTheme.store_id == store.id).first() if store else None
-
-    context = {
-        "request": request,
-        "site": site,
-        "store": store,
-        "page": page,
-        "nav_pages": nav_pages,
-        "theme": theme,
-    }
-    return templates.TemplateResponse(
-        "hosting/public/poc-viewer.html",
-        context,
     )
+
+    # In dev mode, storefront needs /platforms/{code}/ prefix
+    if settings.debug and store_platform and store_platform.platform:
+        platform_code = store_platform.platform.code
+        base_url = f"/platforms/{platform_code}/storefront/{subdomain}"
+    else:
+        base_url = f"/storefront/{subdomain}"
+
+    # Append page slug — storefront needs /{slug} (root has no catch-all)
+    base_url += f"/{page}"
+
+    return RedirectResponse(f"{base_url}?_preview={token}", status_code=302)