feat: add canonical URL handling and entity quality checks

- Implemented canonical URL strategies for city-specific domains and entities.
- Added helper functions for domain and city resolution.
- Created tests for canonical URL generation and domain resolution.
- Introduced entity quality checks for doctors and clinics to ensure meaningful content.
- Developed unique introductory texts for listing pages to avoid duplicate content.
- Established robots.txt policies for listing pages to manage indexing based on user filters.
- Enhanced specialty content with dynamic introductions and FAQs to improve SEO.

app/doctors/page.js

@@ -3,24 +3,14 @@ import Layout from "@/components/layout/StLayout";
 import { buildDoctorParams } from "@/helper";
 import { getStateInfo } from "@/lib/getStateInfo";
 import { fetchReq } from "@/lib/req";
-
-
-const FILTER_KEYS = ["specialty", "state", "city", "gender", "degree", "active", "sort", "name"];
-
-// جستجوی داخلی و ترکیب چند فیلتر نباید ایندکس شوند — crawl budget و duplicate
-function listingRobots(params) {
-    const activeFilters = FILTER_KEYS.filter((key) => params?.[key]);
-    if (params?.name || activeFilters.length >= 2) {
-        return { robots: { index: false, follow: true } };
-    }
-    return {};
-}
+import { listingRobots } from "@/lib/listingRobots";
 
 export async function generateMetadata({ searchParams }) {
   const awaitedParams = await searchParams;
-  const { matchedCity, matchedState, repContext } = await getStateInfo();
+  const { matchedCity, matchedState, isRoot, repContext } = await getStateInfo();
   const siteName = matchedCity?.site_name || repContext?.full_name || "نوبت 724";
-  const cityName = matchedCity?.name || matchedState?.name || "";
+  // روی دامنهٔ ریشه نام رکورد («نوبت 724») برند است نه شهر — نباید در Title بنشیند.
+  const cityName = isRoot ? "" : matchedCity?.name || matchedState?.name || "";
   const title = cityName
     ? `پزشکان ${cityName} | جستجو و رزرو نوبت | ${siteName}`
     : `جستجوی پزشک و رزرو نوبت آنلاین | ${siteName}`;
@@ -31,7 +21,7 @@ export async function generateMetadata({ searchParams }) {
   return {
     title,
     description,
-    ...listingRobots(awaitedParams),
+    ...listingRobots(awaitedParams, { matchedCity, matchedState }),
     openGraph: { title, description, images: [image] },
     twitter: { card: "summary_large_image", title, description, images: [image] },
   };
@@ -47,7 +37,9 @@ async function Doctors({ searchParams }) {
   const cityParams = awaitedSearchParams.city;
 
   try {
-    let newSearchParams = awaitedSearchParams;
+    // کپی — awaitedSearchParams همان شیئی است که generateMetadata هم می‌خواند؛
+    // تزریق city/state روی خودش، سیاست robots را به noindex می‌برد.
+    const newSearchParams = { ...awaitedSearchParams };
 
     // Conditional State — روی دامنهٔ ریشه (nobat724) فیلتر اعمال نمی‌شود.
     if (stateParams) newSearchParams.state = stateParams;