feat: replace SmtpEmailSender with EmailApiEmailSender in api

- EmailApiEmailSender calls email-api via IEmailApiClient Refit client
- HTML bodies built inline for contact/subscribe/file-download emails
- match and job-search emails use DB templates (rendered in caller)
- SmtpSettings moved from api-models to email-api (kept in Models.Settings namespace)
- MailKit removed from api.csproj
- SmtpEmailSender deleted; IEmailSender interface unchanged

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Apis/api/Program.cs

@@ -1,6 +1,8 @@
 using System.Reflection;
 using Api.Services;
 using Api.Services.Contracts;
+using EmailApi.Models.Clients;
+using EmailApi.Models.Settings;
 using Microsoft.EntityFrameworkCore;
 using Models.Settings;
 using MyAi.Data;
@@ -29,10 +31,10 @@ try
     builder.Services.Configure<GoogleSettings>(builder.Configuration.GetSection("Google"));
     builder.Services.Configure<ContactSettings>(builder.Configuration.GetSection("Contact"));
     builder.Services.Configure<SubscribeSettings>(builder.Configuration.GetSection("Subscribe"));
-    builder.Services.Configure<SmtpSettings>(builder.Configuration.GetSection("Smtp"));
     builder.Services.Configure<CaptchaSettings>(builder.Configuration.GetSection("Captcha"));
     builder.Services.Configure<FileStorageSettings>(builder.Configuration.GetSection("FileStorage"));
     builder.Services.Configure<JobSearchLinkSettings>(builder.Configuration.GetSection("JobSearch"));
+    builder.Services.Configure<EmailApiSettings>(builder.Configuration.GetSection("EmailApi"));
 
     builder.Services.AddDbContext<MyAiDbContext>(options =>
     {
@@ -46,9 +48,20 @@ try
     builder.Services.AddSingleton<ITemplateService, DbTemplateService>();
 
     builder.Services.AddHttpClient<ICaptchaVerifier, RecaptchaVerifier>();
-    builder.Services.AddSingleton<IEmailSender, SmtpEmailSender>();
+    builder.Services.AddSingleton<IEmailSender, EmailApiEmailSender>();
     builder.Services.AddSingleton<Microsoft.AspNetCore.StaticFiles.IContentTypeProvider, Microsoft.AspNetCore.StaticFiles.FileExtensionContentTypeProvider>();
 
+    static void ConfigureEmailApiClient(IServiceProvider sp, HttpClient client)
+    {
+        var config = sp.GetRequiredService<IConfiguration>();
+        var baseUrl = config["EmailApi:BaseUrl"] ?? string.Empty;
+        if (!string.IsNullOrWhiteSpace(baseUrl))
+            client.BaseAddress = new Uri(baseUrl.TrimEnd('/') + "/");
+        var key = config["EmailApi:InternalApiKey"];
+        if (!string.IsNullOrWhiteSpace(key) && !client.DefaultRequestHeaders.Contains("X-Internal-Api-Key"))
+            client.DefaultRequestHeaders.Add("X-Internal-Api-Key", key);
+    }
+
     static void ConfigureCvMatcherApiClient(IServiceProvider sp, HttpClient client)
     {
         var config = sp.GetRequiredService<IConfiguration>();
@@ -60,6 +73,9 @@ try
             client.DefaultRequestHeaders.Add("X-Internal-Api-Key", key);
     }
 
+    builder.Services.AddRefitClient<IEmailApiClient>()
+        .ConfigureHttpClient(ConfigureEmailApiClient);
+
     builder.Services.AddRefitClient<Api.Clients.Api.Contracts.ICvMatcherApi>()
         .ConfigureHttpClient(ConfigureCvMatcherApiClient);