Updated PLANS.md, AGENTS.md, and arabic-localization.md to reflect the “foundations now, full translations later” approach and marked progress accordingly.

Implemented localization foundations across backend and frontend (locale settings/middleware, preferred language, i18n wiring, RTL support, minimal Arabic UI strings, Accept-Language).
Added targeted backend and frontend tests plus a risks note for pending full translation coverage.

frontend/src/i18n/en.json

@@ -0,0 +1,23 @@
+{
+  "hero": {
+    "eyebrow": "Salon Booking Platform",
+    "title": "Find, compare, and book top salons near you.",
+    "subtitle": "Search by city or service, compare pricing, and lock in your slot in seconds.",
+    "searchPlaceholder": "Search by salon or service"
+  },
+  "results": {
+    "title": "Salons",
+    "loading": "Loading salons...",
+    "error": "Unable to load salons. Start the backend API to see results.",
+    "empty": "No salons found."
+  },
+  "card": {
+    "noDescription": "No description yet.",
+    "phoneUnavailable": "Phone unavailable"
+  },
+  "locale": {
+    "label": "Language",
+    "arabic": "العربية",
+    "english": "English"
+  }
+}