Add /api/pair-code (auth) + /api/pair (public) endpoints

backend/Program.cs

@@ -1,5 +1,6 @@
 using backend.Auth;
 using backend.Data;
+using backend.Pairing;
 using Microsoft.EntityFrameworkCore;
 
 var builder = WebApplication.CreateBuilder(args);
@@ -10,6 +11,9 @@ builder.Services.AddDbContext<AppDbContext>(opt =>
 builder.Services.AddAppIdentity();
 builder.Services.AddAuthorization();
 
+builder.Services.AddScoped<backend.Devices.DeviceTokenService>();
+builder.Services.AddScoped<backend.Pairing.PairingService>();
+
 var app = builder.Build();
 
 using (var scope = app.Services.CreateScope())
@@ -30,6 +34,7 @@ app.UseAuthentication();
 app.UseAuthorization();
 
 app.MapAuthEndpoints();
+app.MapPairingEndpoints();
 
 app.MapGet("/health", () => Results.Ok(new { ok = true }));