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/doctor/[slug]/loading.js

@@ -1,27 +0,0 @@
-import CircularLoading from "@/app/component/loading/Circular";
-import CustomLoading from "@/app/component/loading/Custom";
-import TextLoading from "@/app/component/loading/Text";
-
-export default function Loading() {
-  return (
-    <div className="padding-responsive pt-[95px] sm:pt-[120px]">
-      <div className="flex flex-col lg:flex-row items-center justify-start gap-[8px] lg:gap-[32px]">
-        <CircularLoading
-          loading
-          width={100}
-          height={100}
-          className="w-[40px] sm:w-[81px] md:w-[123px] lg:w-[164px] h-[40px] sm:h-[81px] md:h-[123px] lg:h-[164px]"
-        />
-        <div className="flex flex-col items-center lg:items-start gap-[8px] lg:gap-[16px]">
-          <TextLoading loading width={90} height={20} />
-          <TextLoading loading width={100} height={20} />
-          <div className="flex items-center justify-start gap-11">
-            <TextLoading loading width={60} height={20} />
-            <TextLoading loading width={120} height={20} />
-          </div>
-          <CustomLoading loading width={160} height={25} />
-        </div>
-      </div>
-    </div>
-  );
-}

app/doctor/[slug]/page.js

@@ -3,7 +3,11 @@ import DoctorPage from "@/components/doctor";
 import Layout from "@/components/layout/StLayout";
 import { notFound } from "next/navigation";
 import { getStateInfo } from "@/lib/getStateInfo";
-import { getRequestOrigin } from "@/lib/getCanonicalUrl";
+import { getEntityOrigin } from "@/lib/getCanonicalUrl";
+import { extractEntityCityId, findCityById } from "@/lib/domainHelpers";
+import { buildDoctorFaq } from "@/lib/specialtyContent";
+import { isThinDoctor } from "@/lib/entityQuality";
+import specialtiesData from "@/data/specialties.json";
 import { safeJsonLd } from "@/lib/sanitize";
 import { imageUrl } from "@/helper";
 
@@ -77,12 +81,14 @@ export async function generateMetadata({ params }) {
       `رزرو نوبت آنلاین دکتر ${doctor.name}${specialtyNames ? " متخصص " + specialtyNames : ""}${doctor.address ? " | " + doctor.address : ""}`.trim()
     ).slice(0, 160);
     const image = imageUrl(doctor.img?.[0]?.url) || FALLBACK_IMG;
-    const isUnclaimed = doctor.owner_status !== "claimed";
+    // C1-b — پزشک به دامنهٔ شهر خودش canonical می‌شود، روی هر دامنه‌ای که سرو شود.
+    const origin = await getEntityOrigin(extractEntityCityId(doctor));
 
     return {
       title,
       description,
-      ...(isUnclaimed && { robots: { index: false, follow: true } }),
+      alternates: { canonical: `${origin}/doctor/${doctor.uuid}` },
+      ...(isThinDoctor(doctor) && { robots: { index: false, follow: true } }),
       openGraph: {
         title,
         description,
@@ -96,20 +102,24 @@ export async function generateMetadata({ params }) {
         images: [image],
       },
     };
-  } catch {
+  } catch (error) {
+    // بازگشت خاموش، canonical و robots صفحه را بی‌صدا به fallback لایه می‌برد — لاگ لازم است.
+    console.error(`[doctor/${slug}] generateMetadata failed:`, error);
     return {};
   }
 }
 
 async function Doctor({ params }) {
   const { slug } = await params;
-  const origin = await getRequestOrigin();
   let comments = null;
   let rateAggregate = { point: 0, satisfaction: 0, averages: [] };
 
   const doctor = await getDoctor(slug);
   if (!doctor) notFound();
 
+  // همان مقصد canonical — تا url/@id و breadcrumb سیگنال متناقض ندهند.
+  const origin = await getEntityOrigin(extractEntityCityId(doctor));
+
   if (doctor) {
     try {
       const [resComments, resRate] = await Promise.all([
@@ -229,23 +239,43 @@ async function Doctor({ params }) {
     : null;
 
   const specialtyLabel = doctor?.specialties?.[0]?.name || "پزشکان";
+  // مقصد تمیز صفحهٔ فرود تخصص؛ اگر تخصص slug نداشت، به لیست پزشکان برمی‌گردیم.
+  const specialtySlug = specialtiesData.find(
+    (item) => item.name === specialtyLabel && item.status === 1
+  )?.slug;
+  const specialtyItem = specialtySlug
+    ? `${origin}/specialties/${specialtySlug}`
+    : `${origin}/doctors`;
+
   const breadcrumbJsonLd = doctor
     ? {
         "@context": "https://schema.org",
         "@type": "BreadcrumbList",
         itemListElement: [
           { "@type": "ListItem", position: 1, name: "خانه", item: origin },
-          {
-            "@type": "ListItem",
-            position: 2,
-            name: specialtyLabel,
-            item: `${origin}/doctors?specialty=${encodeURIComponent(specialtyLabel)}`,
-          },
+          { "@type": "ListItem", position: 2, name: specialtyLabel, item: specialtyItem },
           { "@type": "ListItem", position: 3, name: `دکتر ${doctor.name}` },
         ],
       }
     : null;
 
+  // FAQPage عمداً script مستقل است — اسکیماهای Physician/Review/Geo نباید تحت تأثیر باشند.
+  const doctorCity = findCityById(extractEntityCityId(doctor));
+  const faq = doctor
+    ? buildDoctorFaq(doctor.name, specialtyNames, doctorCity?.name)
+    : [];
+  const faqJsonLd = faq.length
+    ? {
+        "@context": "https://schema.org",
+        "@type": "FAQPage",
+        mainEntity: faq.map((item) => ({
+          "@type": "Question",
+          name: item.question,
+          acceptedAnswer: { "@type": "Answer", text: item.answer },
+        })),
+      }
+    : null;
+
   return (
     <>
       {jsonLd && (
@@ -254,6 +284,12 @@ async function Doctor({ params }) {
           dangerouslySetInnerHTML={{ __html: safeJsonLd(jsonLd) }}
         />
       )}
+      {faqJsonLd && (
+        <script
+          type="application/ld+json"
+          dangerouslySetInnerHTML={{ __html: safeJsonLd(faqJsonLd) }}
+        />
+      )}
       {breadcrumbJsonLd && (
         <script
           type="application/ld+json"
@@ -269,6 +305,7 @@ async function Doctor({ params }) {
           bookableAddressUuids={[...bookableAddressUuids]}
           bookingLocations={bookingLocations}
           slug={slug}
+          faq={faq}
         />
       </Layout>
     </>