feat: Add JWT authentication to backend, configure frontend API client, fix streak layout

src/components/AI/ReadinessGauge.tsx

@@ -1,5 +1,6 @@
 "use client"
 
+import { fetchWithAuth } from "@/lib/apiClient";
 import { useEffect, useState } from "react"
 import { Card, CardContent } from "@/components/ui/card"
 import { TrendingUp, Flame, RefreshCw } from "lucide-react"
@@ -18,7 +19,7 @@ export function ReadinessGauge() {
 
     async function fetchReadiness() {
       try {
-        const res = await fetch(`/api/ai-coach/readiness/${userId}`)
+        const res = await fetchWithAuth(`/api/ai-coach/readiness/${userId}`)
         if (!res.ok) throw new Error("Failed to fetch")
         const json = await res.json()
         setData(json)