Add Infrastructure layer with EF6/EF Core support

Introduced a robust Infrastructure layer for the ECMJobRunner system:
- Added `AGENTS.md` with detailed project documentation.
- Implemented generic repository and unit-of-work patterns.
- Added `CfgProfileRepository`, `ProfileSqlJobRepository`, and `ProfileHistoryRepository`.
- Integrated AutoMapper for DTO-to-entity mapping.
- Added multi-framework support for .NET Framework 4.8 (EF6) and .NET 8.0 (EF Core) using conditional compilation.
- Updated `ECMJobRunner.Infrastructure.csproj` with metadata fixes and dependencies.
- Introduced dependency injection extension for .NET 8.0.
- Enhanced project structure and database context with entity mappings.

ECMJobRunner.Infrastructure/Repositories/ProfileSqlJobRepository.cs

@@ -0,0 +1,22 @@
+using AutoMapper;
+using ECMJobRunner.Domain.Entities;
+using ECMJobRunner.Domain.Interfaces;
+using ECMJobRunner.Infrastructure.Data;
+
+namespace ECMJobRunner.Infrastructure.Repositories
+{
+    /// <summary>
+    /// ProfileSqlJob repository implementation
+    /// </summary>
+    public class ProfileSqlJobRepository : Repository<ProfileSqlJob>, IProfileSqlJobRepository
+    {
+        /// <summary>
+        /// Constructor
+        /// </summary>
+        public ProfileSqlJobRepository(JobRunnerDbContext context, IMapper mapper) : base(context, mapper)
+        {
+        }
+
+        // Entity-specific methods can be added here in the future
+    }
+}