feat: Implement API client and token models with hashing and JWT authentication

- Added ApiClientModel and ApiTokenModel for managing API clients and tokens.
- Introduced ConfigurationDefinitionModel and ConfigurationValueModel for configuration management.
- Created CredentialSecretModel for storing credential secrets.
- Developed DeploymentArtifactModel and DeploymentBatchModel for deployment management.
- Enhanced DeploymentTargetModel and DeploymentTemplateSelectionModel to support template revisions.
- Added TemplateRevisionModel and TemplateVersionModel for versioning templates.
- Implemented ApiClientSecretHasher for secure secret hashing.
- Created ApiTokenService for generating and validating JWT tokens.
- Updated QueueJobService to handle deployment requests with artifacts.
- Configured authentication settings in appsettings.json for JWT and Negotiate authentication.

Models/ApiClientModel.cs

@@ -0,0 +1,28 @@
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Microsoft.SelfService.Portal.Core.API.Models
+{
+    public class ApiClientModel : BaseModel
+    {
+        [Column(Order = 1)]
+        public string ClientId { get; set; } = string.Empty;
+
+        [Column(Order = 2)]
+        public string Name { get; set; } = string.Empty;
+
+        [Column(Order = 3)]
+        public string SecretHash { get; set; } = string.Empty;
+
+        [Column(Order = 4)]
+        public string ScopesJson { get; set; } = "[]";
+
+        [Column(Order = 5)]
+        public bool IsEnabled { get; set; } = true;
+
+        [Column(Order = 6)]
+        public DateTime? ExpiresAt { get; set; }
+
+        [Column(Order = 7)]
+        public DateTime? LastUsedAt { get; set; }
+    }
+}