Added database models

src/Portfolio.Api/DatabaseContext.cs

@@ -0,0 +1,25 @@
+using Microsoft.EntityFrameworkCore;
+using Portfolio.Shared.Models;
+
+namespace Portfolio.Api;
+
+public class DatabaseContext(DbContextOptions<DatabaseContext> options) : DbContext(options) {
+
+    public DbSet<Project> Projects { get; set; }
+
+    public DbSet<Language> Languages { get; set; }
+
+    public DbSet<Technology> Technologies { get; set; }
+
+    public DbSet<TimelineEntry> Timeline { get; set; }
+
+    public DbSet<About> About { get; set; }
+
+    protected override void OnModelCreating(ModelBuilder modelBuilder) {
+        modelBuilder.Entity<Project>()
+            .HasMany(p => p.Languages)
+            .WithMany()
+            .UsingEntity("ProjectLanguage");
+    }
+    
+}