feat: complete dynamic menu system across all frontends

- Add "Merchant Frontend" tab to admin menu-config page
- Merchant render endpoint now respects AdminMenuConfig visibility
  via get_merchant_primary_platform_id() platform resolution
- New store menu render endpoint (GET /store/core/menu/render/store)
  with platform-scoped visibility and store_code interpolation
- Store sidebar migrated from hardcoded Jinja2 macros to dynamic
  Alpine.js x-for rendering with loading skeleton and fallback
- Store init-alpine.js: add loadMenuConfig(), expandSectionForCurrentPage()
- Include store page route fixes, login template updates, and tests

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

app/modules/core/routes/api/merchant_menu.py

@@ -101,10 +101,16 @@ async def get_rendered_merchant_menu(
     # Get union of enabled module codes across all subscribed platforms
     enabled_codes = menu_service.get_merchant_enabled_module_codes(db, merchant.id)
 
-    # Get filtered menu using enabled_module_codes override
+    # Resolve primary platform for AdminMenuConfig visibility lookup
+    primary_platform_id = menu_service.get_merchant_primary_platform_id(
+        db, merchant.id
+    )
+
+    # Get filtered menu using enabled_module_codes override + platform visibility
     menu = menu_service.get_menu_for_rendering(
         db=db,
         frontend_type=FrontendType.MERCHANT,
+        platform_id=primary_platform_id,
         enabled_module_codes=enabled_codes,
     )
 

app/modules/core/routes/api/store.py

@@ -5,15 +5,18 @@ Core module store API routes.
 Aggregates:
 - /dashboard/* - Dashboard statistics
 - /settings/* - Store settings management
+- /menu/* - Store menu rendering
 """
 
 from fastapi import APIRouter
 
 from .store_dashboard import store_dashboard_router
+from .store_menu import store_menu_router
 from .store_settings import store_settings_router
 
 store_router = APIRouter()
 
 # Aggregate sub-routers
 store_router.include_router(store_dashboard_router, tags=["store-dashboard"])
+store_router.include_router(store_menu_router, tags=["store-menu"])
 store_router.include_router(store_settings_router, tags=["store-settings"])

app/modules/core/routes/api/store_menu.py

@@ -0,0 +1,139 @@
+# app/modules/core/routes/api/store_menu.py
+"""
+Store menu rendering endpoint.
+
+Provides the dynamic sidebar menu for the store portal:
+- GET /menu/render/store - Get rendered store menu for current user
+
+Menu sections are driven by module definitions (FrontendType.STORE).
+Only modules enabled on the store's platform will appear in the sidebar.
+Visibility is controlled by AdminMenuConfig records for the platform.
+"""
+
+import logging
+from typing import Any
+
+from fastapi import APIRouter, Depends, Request
+from pydantic import BaseModel
+from sqlalchemy.orm import Session
+
+from app.api.deps import get_current_store_api
+from app.core.database import get_db
+from app.modules.core.services.menu_service import menu_service
+from app.modules.enums import FrontendType
+from app.modules.tenancy.services.store_service import store_service
+from app.utils.i18n import translate
+from models.schema.auth import UserContext
+
+logger = logging.getLogger(__name__)
+
+store_menu_router = APIRouter(prefix="/menu")
+
+
+# =============================================================================
+# Schemas
+# =============================================================================
+
+
+class MenuSectionResponse(BaseModel):
+    """Menu section for rendering."""
+
+    id: str
+    label: str | None = None
+    items: list[dict[str, Any]]
+
+
+class RenderedMenuResponse(BaseModel):
+    """Rendered menu for frontend."""
+
+    frontend_type: str
+    sections: list[MenuSectionResponse]
+
+
+# =============================================================================
+# Helpers
+# =============================================================================
+
+
+def _translate_label(label_key: str | None, language: str) -> str | None:
+    """Translate a label key, falling back to a readable version of the key."""
+    if not label_key:
+        return None
+
+    translated = translate(label_key, language=language)
+
+    # If translation returned the key itself, create a readable fallback
+    if translated == label_key:
+        parts = label_key.split(".")
+        last_part = parts[-1]
+        return last_part.replace("_", " ").title()
+
+    return translated
+
+
+# =============================================================================
+# Endpoint
+# =============================================================================
+
+
+@store_menu_router.get("/render/store", response_model=RenderedMenuResponse)
+async def get_rendered_store_menu(
+    request: Request,
+    db: Session = Depends(get_db),
+    current_user: UserContext = Depends(get_current_store_api),
+):
+    """
+    Get the rendered store menu for the current user.
+
+    Returns the filtered menu structure based on:
+    - Modules enabled on the store's platform
+    - AdminMenuConfig visibility for the platform
+    - Store code for URL placeholder replacement
+
+    Used by the store frontend to render the sidebar dynamically.
+    """
+    # Get the store from the JWT token's store context
+    store = store_service.get_store_by_id(db, current_user.token_store_id)
+
+    # Resolve the store's platform via service layer
+    platform_id = menu_service.get_store_primary_platform_id(db, store.id)
+
+    # Get filtered menu with platform visibility and store_code interpolation
+    menu = menu_service.get_menu_for_rendering(
+        db=db,
+        frontend_type=FrontendType.STORE,
+        platform_id=platform_id,
+        store_code=store.subdomain,
+    )
+
+    # Resolve language
+    language = current_user.preferred_language or getattr(
+        request.state, "language", "en"
+    )
+
+    # Translate section and item labels
+    sections = []
+    for section in menu:
+        translated_items = []
+        for item in section.items:
+            translated_items.append(
+                {
+                    "id": item.id,
+                    "label": _translate_label(item.label_key, language),
+                    "icon": item.icon,
+                    "url": item.route,
+                }
+            )
+
+        sections.append(
+            MenuSectionResponse(
+                id=section.id,
+                label=_translate_label(section.label_key, language),
+                items=translated_items,
+            )
+        )
+
+    return RenderedMenuResponse(
+        frontend_type=FrontendType.STORE.value,
+        sections=sections,
+    )