fix: move orchestrate endpoints out of admin router

- Create backend/app/api/orchestrate.py — new router for workflow steps
  (scrape, generate, email, reminder, deadline, finalize) without admin auth.
- Remove orchestrate endpoints from backend/app/api/admin.py.
- Register orchestrate router in main.py under /api/orchestrate.
- Update frontend api/index.ts to call /orchestrate/{step} instead of
  /admin/orchestrate/{step}.

This lets family members trigger vote emails without an admin bearer token.

backend/app/main.py

@@ -35,6 +35,7 @@ from app.api import recipes as recipes_api
 from app.api import never_suggest as never_suggest_api
 from app.api import meal_plans as meal_plans_api
 from app.api import feedback as feedback_api
+from app.api import orchestrate as orchestrate_api
 
 app.include_router(auth.router, prefix="/api/auth", tags=["auth"])
 app.include_router(profile.router, prefix="/api/profile", tags=["profile"])
@@ -42,6 +43,7 @@ app.include_router(meals.router, prefix="/api/meals", tags=["meals"])
 app.include_router(shopping_list.router, prefix="/api/shopping-list", tags=["shopping-list"])
 app.include_router(pantry.router, prefix="/api/pantry", tags=["pantry"])
 app.include_router(admin.router, prefix="/api/admin", tags=["admin"])
+app.include_router(orchestrate_api.router, prefix="/api/orchestrate", tags=["orchestrate"])
 app.include_router(ingredients_api.public_router)
 app.include_router(ingredients_api.admin_router)
 app.include_router(ingredients_api._match_admin_router)