[SM-1293] Add endpoint to fetch secret's access policies (#4146)

* Add authz handling for secret access policy reads

* Add the ability to fetch secret access polices from the repository

* refactor response models

* Add new endpoint

src/Core/SecretsManager/Models/Data/SecretAccessPolicies.cs

@@ -0,0 +1,35 @@
+#nullable enable
+using Bit.Core.SecretsManager.Entities;
+
+namespace Bit.Core.SecretsManager.Models.Data;
+
+public class SecretAccessPolicies
+{
+    public SecretAccessPolicies(Guid secretId, Guid organizationId, List<BaseAccessPolicy> policies)
+    {
+        SecretId = secretId;
+        OrganizationId = organizationId;
+
+        UserAccessPolicies = policies
+            .OfType<UserSecretAccessPolicy>()
+            .ToList();
+
+        GroupAccessPolicies = policies
+            .OfType<GroupSecretAccessPolicy>()
+            .ToList();
+
+        ServiceAccountAccessPolicies = policies
+            .OfType<ServiceAccountSecretAccessPolicy>()
+            .ToList();
+    }
+
+    public SecretAccessPolicies()
+    {
+    }
+
+    public Guid SecretId { get; set; }
+    public Guid OrganizationId { get; set; }
+    public IEnumerable<UserSecretAccessPolicy> UserAccessPolicies { get; set; } = [];
+    public IEnumerable<GroupSecretAccessPolicy> GroupAccessPolicies { get; set; } = [];
+    public IEnumerable<ServiceAccountSecretAccessPolicy> ServiceAccountAccessPolicies { get; set; } = [];
+}