⭐ feat(www): Finish up on the onboarding (#210)

Merging this prematurely to make sure the team is on the same boat... like dang! We need to find a better way to do this. 

Plus it has become too big

packages/steam/DBContext.cs

@@ -0,0 +1,18 @@
+using Microsoft.EntityFrameworkCore;
+
+public class SteamDbContext : DbContext
+{
+    public DbSet<SteamUserCredential> SteamUserCredentials { get; set; }
+    
+    public SteamDbContext(DbContextOptions<SteamDbContext> options) : base(options)
+    {
+    }
+    
+    protected override void OnModelCreating(ModelBuilder modelBuilder)
+    {
+        // Create a unique index on TeamId and UserId
+        modelBuilder.Entity<SteamUserCredential>()
+            .HasIndex(c => new { c.TeamId, c.UserId })
+            .IsUnique();
+    }
+}