Support multi-targeting and add NuGet metadata

Updated `EnvelopeGenerator.DependencyInjection.csproj` to support multiple target frameworks (`net7.0`, `net8.0`, `net9.0`) for broader compatibility. Added NuGet package metadata to enable publishing, including details like `PackageId`, `Authors`, and `RepositoryUrl`.

Upgraded `Microsoft.Extensions.Configuration.Abstractions` and `Microsoft.Extensions.DependencyInjection.Abstractions` to version `9.0.6`. Added a project reference to `EnvelopeGenerator.Domain`.

Modified `EnvelopeGenerator.sln` to adjust the build configuration for the project with GUID `{90FE0312-8C38-4347-9EA2-0A719E255D5C}`, setting `Debug` to use the `Release` configuration.

EnvelopeGenerator.DependencyInjection/DependencyInjection.cs

@@ -0,0 +1,108 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using EnvelopeGenerator.Application;
+using EnvelopeGenerator.Application.Common.Interfaces.Services;
+using EnvelopeGenerator.Application.Services;
+using EnvelopeGenerator.Infrastructure;
+
+namespace EnvelopeGenerator.DependencyInjection;
+
+/// <summary>
+/// Extension methods for registering EnvelopeGenerator services into an <see cref="IServiceCollection"/>.
+/// Use <see cref="AddEnvelopeGenerator"/> as the single entry-point for projects that need both the
+/// application layer (MediatR, AutoMapper, CRUD services, configuration sections) and the infrastructure
+/// layer (repositories, DbContext, SQL executors).
+/// For projects that do not need a database (e.g. lightweight API gateways or unit-test hosts), use
+/// <see cref="AddEnvelopeGeneratorCore"/> to register only the application layer.
+/// </summary>
+public static class DependencyInjection
+{
+    /// <summary>
+    /// Registers the full EnvelopeGenerator stack – application <em>and</em> infrastructure services – into
+    /// the provided <see cref="IServiceCollection"/>.
+    /// <para>
+    /// Internally this calls <c>AddEnvelopeGeneratorServices</c> (application layer) and
+    /// <c>AddEnvelopeGeneratorInfrastructureServices</c> (infrastructure layer).
+    /// A <see cref="Microsoft.EntityFrameworkCore.DbContext"/> and / or <c>DbTriggerParams</c> must be
+    /// configured through <paramref name="infrastructureOptions"/>; without it no database connection will
+    /// be established at runtime.
+    /// </para>
+    /// </summary>
+    /// <param name="services">Service collection to register services into.</param>
+    /// <param name="configuration">
+    ///     Application configuration. Used to bind <c>DispatcherParams</c>, <c>MailParams</c>,
+    ///     <c>AuthenticatorParams</c>, <c>TotpSmsParams</c>, <c>GtxMessagingParams</c> and other
+    ///     application-level option sections.
+    /// </param>
+    /// <param name="infrastructureOptions">
+    ///     Optional callback to configure the infrastructure layer registration.
+    ///     Typical usage:
+    ///     <code>
+    ///     services.AddEnvelopeGenerator(config, opt =>
+    ///     {
+    ///         opt.AddDbContext(o => o.UseSqlServer(connectionString));
+    ///         opt.AddDbTriggerParams(config);
+    ///     });
+    ///     </code>
+    /// </param>
+    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
+#pragma warning disable CS0618 // AddEnvelopeGeneratorServices / AddEnvelopeGeneratorInfrastructureServices are intentionally wrapped here
+    public static IServiceCollection AddEnvelopeGenerator(
+        this IServiceCollection services,
+        IConfiguration configuration,
+        Action<EnvelopeGenerator.Infrastructure.DependencyInjection.Config>? infrastructureOptions = null)
+    {
+        // Application layer: CRUD services, MediatR, AutoMapper, configuration sections.
+        services.AddEnvelopeGeneratorServices(configuration);
+
+        // Infrastructure layer: repositories, DbContext, Dapper type maps, SQL executors.
+        services.AddEnvelopeGeneratorInfrastructureServices(opt =>
+        {
+            infrastructureOptions?.Invoke(opt);
+        });
+
+        return services;
+    }
+#pragma warning restore CS0618
+
+    /// <summary>
+    /// Registers only the <em>application</em> layer services (MediatR handlers, AutoMapper profiles,
+    /// CRUD services, configuration sections) without any infrastructure / database dependencies.
+    /// <para>
+    /// Useful for projects that already manage their own DbContext or do not require direct database
+    /// access, such as lightweight API gateways, console tools or unit/integration test hosts that
+    /// use an in-memory database configured elsewhere.
+    /// </para>
+    /// </summary>
+    /// <param name="services">Service collection to register services into.</param>
+    /// <param name="configuration">Application configuration used to bind application-level option sections.</param>
+    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
+#pragma warning disable CS0618
+    public static IServiceCollection AddEnvelopeGeneratorCore(
+        this IServiceCollection services,
+        IConfiguration configuration)
+    {
+        services.AddEnvelopeGeneratorServices(configuration);
+        return services;
+    }
+#pragma warning restore CS0618
+
+    /// <summary>
+    /// Registers <see cref="EnvelopeMailService"/> as the <see cref="IEnvelopeMailService"/> scoped
+    /// implementation.
+    /// <para>
+    /// Call this in addition to <see cref="AddEnvelopeGenerator"/> when the consuming project needs to
+    /// send envelope e-mails directly (e.g. a Worker Service or the Web project). Projects that rely
+    /// purely on MediatR commands to trigger mail delivery do not need to call this.
+    /// </para>
+    /// </summary>
+    /// <param name="services">Service collection to register services into.</param>
+    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
+#pragma warning disable CS0618
+    public static IServiceCollection AddEnvelopeMailService(this IServiceCollection services)
+    {
+        services.AddScoped<IEnvelopeMailService, EnvelopeMailService>();
+        return services;
+    }
+#pragma warning restore CS0618
+}

EnvelopeGenerator.DependencyInjection/EnvelopeGenerator.DependencyInjection.csproj

@@ -0,0 +1,39 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>net7.0;net8.0;net9.0</TargetFrameworks>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <!-- NuGet package metadata -->
+    <PackageId>EnvelopeGenerator</PackageId>
+    <Authors>Digital Data GmbH</Authors>
+    <Company>Digital Data GmbH</Company>
+    <Product>EnvelopeGenerator</Product>
+    <Description>
+      Envelope Generator ist eine Bibliothek zur Verwaltung und Verarbeitung digitaler Umschläge (Envelopes).
+      Dieses Paket enthält die Dependency-Injection-Erweiterungsmethoden und bündelt die Application-
+      sowie Infrastructure-Schicht in einer einzigen NuGet-Referenz.
+    </Description>
+    <Copyright>Copyright 2024 Digital Data GmbH</Copyright>
+    <RepositoryUrl>http://git.dd:3000/AppStd/EnvelopeGenerator.git</RepositoryUrl>
+    <PackageTags>digital data envelope generator di dependency injection</PackageTags>
+    <PackageRequireLicenseAcceptance>false</PackageRequireLicenseAcceptance>
+    <Version>1.0.0</Version>
+    <AssemblyVersion>1.0.0</AssemblyVersion>
+    <FileVersion>1.0.0</FileVersion>
+    <GeneratePackageOnBuild>false</GeneratePackageOnBuild>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="9.0.6" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="9.0.6" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\EnvelopeGenerator.Application\EnvelopeGenerator.Application.csproj" />
+    <ProjectReference Include="..\EnvelopeGenerator.Domain\EnvelopeGenerator.Domain.csproj" />
+    <ProjectReference Include="..\EnvelopeGenerator.Infrastructure\EnvelopeGenerator.Infrastructure.csproj" />
+  </ItemGroup>
+
+</Project>

EnvelopeGenerator.sln

@@ -35,6 +35,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EnvelopeGenerator.Tests", "
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EnvelopeGenerator.API", "EnvelopeGenerator.API\EnvelopeGenerator.API.csproj", "{EC768913-6270-14F4-1DD3-69C87A659462}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EnvelopeGenerator.DependencyInjection", "EnvelopeGenerator.DependencyInjection\EnvelopeGenerator.DependencyInjection.csproj", "{90FE0312-8C38-4347-9EA2-0A719E255D5C}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -85,6 +87,10 @@ Global
 		{EC768913-6270-14F4-1DD3-69C87A659462}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{EC768913-6270-14F4-1DD3-69C87A659462}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{EC768913-6270-14F4-1DD3-69C87A659462}.Release|Any CPU.Build.0 = Release|Any CPU
+		{90FE0312-8C38-4347-9EA2-0A719E255D5C}.Debug|Any CPU.ActiveCfg = Release|Any CPU
+		{90FE0312-8C38-4347-9EA2-0A719E255D5C}.Debug|Any CPU.Build.0 = Release|Any CPU
+		{90FE0312-8C38-4347-9EA2-0A719E255D5C}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{90FE0312-8C38-4347-9EA2-0A719E255D5C}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -104,6 +110,7 @@ Global
 		{211619F5-AE25-4BA5-A552-BACAFE0632D3} = {9943209E-1744-4944-B1BA-4F87FC1A0EEB}
 		{224C4845-1CDE-22B7-F3A9-1FF9297F70E8} = {0CBC2432-A561-4440-89BC-671B66A24146}
 		{EC768913-6270-14F4-1DD3-69C87A659462} = {E3C758DC-914D-4B7E-8457-0813F1FDB0CB}
+		{90FE0312-8C38-4347-9EA2-0A719E255D5C} = {E3C758DC-914D-4B7E-8457-0813F1FDB0CB}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {73E60370-756D-45AD-A19A-C40A02DACCC7}