feat: connect Apply Now to applications API

Frontend changes:
- Add applicationsApi with create() and getByJob() in api.ts
- Update apply/page.tsx to fetch job from API and submit to backend
- Fix job detail page requirements null check
- Use ApiJob type instead of mock Job type
- Replace job.company with job.companyName throughout

Note: Backend has type mismatch issues that need fixing:
- jobs endpoint: varchar vs integer comparison
- applications: null id constraint

frontend/src/app/jobs/[id]/apply/page.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState, use } from "react";
+import { useState, use, useEffect } from "react";
 import { useRouter } from "next/navigation";
 import Link from "next/link";
 import { motion, AnimatePresence } from "framer-motion";
@@ -15,6 +15,7 @@ import {
   MessageSquare,
   Save,
   ArrowLeft,
+  Loader2,
 } from "lucide-react";
 
 import { Button } from "@/components/ui/button";
@@ -42,7 +43,7 @@ import { Separator } from "@/components/ui/separator";
 import { Navbar } from "@/components/navbar";
 import { Footer } from "@/components/footer";
 import { useNotify } from "@/contexts/notification-context";
-import { mockJobs } from "@/lib/mock-data";
+import { jobsApi, applicationsApi, type ApiJob } from "@/lib/api";
 
 // Step definitions
 const steps = [
@@ -65,9 +66,8 @@ export default function JobApplicationPage({
   const notify = useNotify();
   const [currentStep, setCurrentStep] = useState(1);
   const [isSubmitting, setIsSubmitting] = useState(false);
-
-  // Find job details
-  const job = mockJobs.find((j) => j.id === id) || mockJobs[0];
+  const [job, setJob] = useState<ApiJob | null>(null);
+  const [loading, setLoading] = useState(true);
 
   // Form state
   const [formData, setFormData] = useState({
@@ -161,17 +161,56 @@ export default function JobApplicationPage({
     }
   };
 
+  useEffect(() => {
+    async function fetchJob() {
+      try {
+        setLoading(true);
+        const response = await jobsApi.getById(id);
+        if (response) {
+          setJob(response);
+        }
+      } catch (err) {
+        console.error("Error fetching job:", err);
+        notify.error("Error", "Failed to load job details");
+      } finally {
+        setLoading(false);
+      }
+    }
+    fetchJob();
+  }, [id, notify]);
+
   const handleSubmit = async () => {
     setIsSubmitting(true);
-    // Simulate API call
-    await new Promise((resolve) => setTimeout(resolve, 2000));
+    try {
+      await applicationsApi.create({
+        jobId: id,
+        name: formData.fullName,
+        email: formData.email,
+        phone: formData.phone,
+        linkedin: formData.linkedin,
+        coverLetter: formData.coverLetter,
+        portfolioUrl: formData.portfolioUrl,
+        salaryExpectation: formData.salaryExpectation,
+        hasExperience: formData.hasExperience,
+        whyUs: formData.whyUs,
+        availability: formData.availability,
+      });
 
-    notify.success(
-      "Application submitted!",
-      `Good luck! Your application for ${job.title} has been received.`
-    );
+      notify.success(
+        "Application submitted!",
+        `Good luck! Your application for ${job?.title || 'this position'} has been received.`
+      );
 
-    router.push("/dashboard/my-applications");
+      router.push("/dashboard/my-applications");
+    } catch (error: any) {
+      console.error("Submit error:", error);
+      notify.error(
+        "Error submitting",
+        error.message || "Please try again later."
+      );
+    } finally {
+      setIsSubmitting(false);
+    }
   };
 
   const handleSaveDraft = () => {
@@ -206,7 +245,7 @@ export default function JobApplicationPage({
                   Application: {job.title}
                 </h1>
                 <p className="text-muted-foreground mt-1">
-                  {job.company} • {job.location}
+                  {job.companyName || 'Company'} • {job.location || 'Remote'}
                 </p>
               </div>
               <div className="text-sm font-medium bg-primary/10 text-primary px-3 py-1 rounded-full self-start md:self-center">
@@ -241,10 +280,10 @@ export default function JobApplicationPage({
                   <div
                     key={step.id}
                     className={`flex flex-col items-center gap-2 ${isActive
-                        ? "text-primary"
-                        : isCompleted
-                          ? "text-primary/60"
-                          : "text-muted-foreground"
+                      ? "text-primary"
+                      : isCompleted
+                        ? "text-primary/60"
+                        : "text-muted-foreground"
                       }`}
                   >
                     <div
@@ -505,7 +544,7 @@ export default function JobApplicationPage({
                       <div className="space-y-6">
                         <div className="space-y-2">
                           <Label htmlFor="whyUs">
-                            Why do you want to work at {job.company}? *
+                            Why do you want to work at {job.companyName || 'this company'}? *
                           </Label>
                           <Textarea
                             id="whyUs"

frontend/src/app/jobs/[id]/page.tsx

@@ -15,7 +15,7 @@ import {
 import { Badge } from "@/components/ui/badge";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
 import { Separator } from "@/components/ui/separator";
-import { jobsApi, transformJob, type Job } from "@/lib/api";
+import { jobsApi, type ApiJob } from "@/lib/api";
 import {
   MapPin,
   Briefcase,
@@ -48,7 +48,7 @@ export default function JobDetailPage({
   const router = useRouter();
   const [isFavorited, setIsFavorited] = useState(false);
   const [isBookmarked, setIsBookmarked] = useState(false);
-  const [job, setJob] = useState<Job | null>(null);
+  const [job, setJob] = useState<ApiJob | null>(null);
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
 
@@ -57,8 +57,8 @@ export default function JobDetailPage({
       try {
         setLoading(true);
         const response = await jobsApi.getById(id);
-        if (response.data) {
-          setJob(transformJob(response.data));
+        if (response) {
+          setJob(response);
         } else {
           setError("Job not found");
         }
@@ -362,12 +362,16 @@ export default function JobDetailPage({
                     </CardHeader>
                     <CardContent>
                       <div className="grid gap-3">
-                        {job.requirements.map((req, index) => (
-                          <div key={index} className="flex items-start gap-3">
-                            <CheckCircle2 className="h-5 w-5 text-primary mt-0.5 shrink-0" />
-                            <span className="text-muted-foreground">{req}</span>
-                          </div>
-                        ))}
+                        {job.requirements && Array.isArray(job.requirements) ? (
+                          job.requirements.map((req, index) => (
+                            <div key={index} className="flex items-start gap-3">
+                              <CheckCircle2 className="h-5 w-5 text-primary mt-0.5 shrink-0" />
+                              <span className="text-muted-foreground">{String(req)}</span>
+                            </div>
+                          ))
+                        ) : (
+                          <p className="text-muted-foreground">No specific requirements listed.</p>
+                        )}
                       </div>
                     </CardContent>
                   </Card>

frontend/src/lib/api.ts

@@ -197,6 +197,66 @@ export const jobsApi = {
     },
 };
 
+// Applications API
+export interface CreateApplicationRequest {
+    jobId: string;
+    userId?: string;
+    name: string;
+    email: string;
+    phone: string;
+    linkedin?: string;
+    coverLetter?: string;
+    portfolioUrl?: string;
+    resumeUrl?: string;
+    salaryExpectation?: string;
+    hasExperience?: string;
+    whyUs?: string;
+    availability?: string[];
+}
+
+export interface Application {
+    id: number;
+    jobId: number;
+    userId?: number;
+    name?: string;
+    email?: string;
+    phone?: string;
+    status: string;
+    createdAt: string;
+}
+
+export const applicationsApi = {
+    create: async (data: CreateApplicationRequest) => {
+        logCrudAction("create", "applications", data);
+        // Map frontend data to backend DTO
+        const payload = {
+            jobId: parseInt(data.jobId) || 0,
+            name: data.name,
+            email: data.email,
+            phone: data.phone,
+            whatsapp: data.phone,
+            message: data.coverLetter || data.whyUs,
+            resumeUrl: data.resumeUrl,
+            documents: {
+                linkedin: data.linkedin,
+                portfolio: data.portfolioUrl,
+                salaryExpectation: data.salaryExpectation,
+                hasExperience: data.hasExperience,
+                availability: data.availability,
+            }
+        };
+        return apiRequest<Application>('/applications', {
+            method: 'POST',
+            body: JSON.stringify(payload),
+        });
+    },
+
+    getByJob: async (jobId: string) => {
+        logCrudAction("read", "applications", { jobId });
+        return apiRequest<Application[]>(`/applications?jobId=${jobId}`);
+    },
+};
+
 // Admin Backoffice API
 export interface AdminRoleAccess {
     role: string;