ChangeFeed: Adds Full Fidelity Change Feed APIs to GA surface

Removes #if PREVIEW guards from 7 types/members to make them
unconditionally public, promoting the AllVersionsAndDeletes mode
from Preview to GA:

1. ChangeFeedMode.AllVersionsAndDeletes
2. ChangeFeedItem<T>
3. ChangeFeedMetadata
4. ChangeFeedOperationType
5. ChangeFeedPolicy
6. ChangeFeedPolicyDefinition
7. ContainerProperties.ChangeFeedPolicy
8. ContainerBuilder.WithChangeFeedPolicy

Updates GA and Preview API contract files accordingly.

Closes #5814

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: ananth7592

Microsoft.Azure.Cosmos/contracts/API_3.59.0.txt

@@ -44,11 +44,42 @@ namespace Microsoft.Azure.Cosmos
         public ChangeFeedEstimatorRequestOptions();
         public Nullable<int> MaxItemCount { get; set; }
     }
+    public class ChangeFeedItem<T>
+    {
+        public ChangeFeedItem();
+        public T Current { get; set; }
+        public ChangeFeedMetadata Metadata { get; set; }
+        public T Previous { get; set; }
+    }
+    public class ChangeFeedMetadata
+    {
+        public ChangeFeedMetadata();
+        public DateTime ConflictResolutionTimestamp { get; }
+        public string Id { get; }
+        public bool IsTimeToLiveExpired { get; }
+        public long Lsn { get; }
+        public ChangeFeedOperationType OperationType { get; }
+        public Dictionary<string, object> PartitionKey { get; }
+        public long PreviousLsn { get; }
+    }
     public abstract class ChangeFeedMode
     {
+        public static ChangeFeedMode AllVersionsAndDeletes { get; }
         public static ChangeFeedMode Incremental { get; }
         public static ChangeFeedMode LatestVersion { get; }
     }
+    public enum ChangeFeedOperationType
+    {
+        Create = 0,
+        Delete = 2,
+        Replace = 1,
+    }
+    public sealed class ChangeFeedPolicy
+    {
+        public ChangeFeedPolicy();
+        public static TimeSpan FullFidelityNoRetention { get; }
+        public TimeSpan FullFidelityRetention { get; set; }
+    }
     public abstract class ChangeFeedProcessor
     {
         protected ChangeFeedProcessor();
@@ -239,6 +270,7 @@ namespace Microsoft.Azure.Cosmos
         public abstract ChangeFeedProcessorBuilder GetChangeFeedEstimatorBuilder(string processorName, Container.ChangesEstimationHandler estimationDelegate, Nullable<TimeSpan> estimationPeriod=default(Nullable<TimeSpan>));
         public abstract FeedIterator<T> GetChangeFeedIterator<T>(ChangeFeedStartFrom changeFeedStartFrom, ChangeFeedMode changeFeedMode, ChangeFeedRequestOptions changeFeedRequestOptions=null);
         public abstract ChangeFeedProcessorBuilder GetChangeFeedProcessorBuilder(string processorName, Container.ChangeFeedStreamHandler onChangesDelegate);
+        public abstract ChangeFeedProcessorBuilder GetChangeFeedProcessorBuilderWithAllVersionsAndDeletes<T>(string processorName, Container.ChangeFeedHandler<ChangeFeedItem<T>> onChangesDelegate);
         public abstract ChangeFeedProcessorBuilder GetChangeFeedProcessorBuilderWithManualCheckpoint(string processorName, Container.ChangeFeedStreamHandlerWithManualCheckpoint onChangesDelegate);
         public abstract ChangeFeedProcessorBuilder GetChangeFeedProcessorBuilderWithManualCheckpoint<T>(string processorName, Container.ChangeFeedHandlerWithManualCheckpoint<T> onChangesDelegate);
         public abstract ChangeFeedProcessorBuilder GetChangeFeedProcessorBuilder<T>(string processorName, Container.ChangeFeedHandler<T> onChangesDelegate);
@@ -286,6 +318,7 @@ namespace Microsoft.Azure.Cosmos
         public ContainerProperties(string id, IReadOnlyList<string> partitionKeyPaths);
         public ContainerProperties(string id, string partitionKeyPath);
         public Nullable<int> AnalyticalStoreTimeToLiveInSeconds { get; set; }
+        public ChangeFeedPolicy ChangeFeedPolicy { get; set; }
         public ClientEncryptionPolicy ClientEncryptionPolicy { get; set; }
         public Collection<ComputedProperty> ComputedProperties { get; set; }
         public ConflictResolutionPolicy ConflictResolutionPolicy { get; set; }
@@ -1274,6 +1307,10 @@ namespace Microsoft.Azure.Cosmos.FaultInjection
 }
 namespace Microsoft.Azure.Cosmos.Fluent
 {
+    public class ChangeFeedPolicyDefinition
+    {
+        public ContainerBuilder Attach();
+    }
     public sealed class ClientEncryptionPolicyDefinition
     {
         public ContainerBuilder Attach();
@@ -1305,6 +1342,7 @@ namespace Microsoft.Azure.Cosmos.Fluent
         public Task<ContainerResponse> CreateAsync(Nullable<int> throughput=default(Nullable<int>), CancellationToken cancellationToken=default(CancellationToken));
         public Task<ContainerResponse> CreateIfNotExistsAsync(ThroughputProperties throughputProperties, CancellationToken cancellationToken=default(CancellationToken));
         public Task<ContainerResponse> CreateIfNotExistsAsync(Nullable<int> throughput=default(Nullable<int>), CancellationToken cancellationToken=default(CancellationToken));
+        public ChangeFeedPolicyDefinition WithChangeFeedPolicy(TimeSpan retention);
         public ClientEncryptionPolicyDefinition WithClientEncryptionPolicy();
         public ClientEncryptionPolicyDefinition WithClientEncryptionPolicy(int policyFormatVersion);
         public ConflictResolutionDefinition WithConflictResolution();

Microsoft.Azure.Cosmos/src/ChangeFeed/ChangeFeedMode.cs

@@ -53,11 +53,6 @@ internal ChangeFeedMode()
         /// but no events for deletes or intermediary updates would be included.
         /// </remarks>
         /// <returns>A <see cref="ChangeFeedMode"/>  to receive notifications for insertions, updates, and delete operations.</returns>
-#if PREVIEW
-        public
-#else
-        internal
-#endif
-        static ChangeFeedMode AllVersionsAndDeletes => ChangeFeedModeFullFidelity.Instance;
+        public static ChangeFeedMode AllVersionsAndDeletes => ChangeFeedModeFullFidelity.Instance;
     }
 }

Microsoft.Azure.Cosmos/src/Fluent/Settings/ChangeFeedPolicyDefinition.cs

@@ -9,12 +9,7 @@ namespace Microsoft.Azure.Cosmos.Fluent
     /// <summary>
     /// <see cref="ChangeFeedPolicy"/> fluent definition.
     /// </summary>
-#if PREVIEW
-    public
-#else
-    internal
-#endif
-    class ChangeFeedPolicyDefinition
+    public class ChangeFeedPolicyDefinition
     {
         private readonly ContainerBuilder parent;
         private readonly Action<ChangeFeedPolicy> attachCallback;

Microsoft.Azure.Cosmos/src/Fluent/Settings/ContainerBuilder.cs

@@ -78,12 +78,7 @@ public ConflictResolutionDefinition WithConflictResolution()
         /// </summary>
         /// <param name="retention"> Indicates for how long operation logs have to be retained. <see cref="ChangeFeedPolicy.FullFidelityRetention"/>.</param>
         /// <returns>An instance of <see cref="ChangeFeedPolicyDefinition"/>.</returns>
-#if PREVIEW
-        public
-#else
-        internal
-#endif
-        ChangeFeedPolicyDefinition WithChangeFeedPolicy(TimeSpan retention)
+        public ChangeFeedPolicyDefinition WithChangeFeedPolicy(TimeSpan retention)
         {
             return new ChangeFeedPolicyDefinition(
                 this,

Microsoft.Azure.Cosmos/src/Resource/FullFidelity/ChangeFeedItem.cs

@@ -49,12 +49,7 @@ namespace Microsoft.Azure.Cosmos
     /// </code>
     /// </example>
     /// <remarks><see cref="ChangeFeedItem{T}"/> is an optional helper class that uses Newtonsoft serialization libraries. Users are welcome to create their own custom helper class.</remarks>
-#if PREVIEW
-    public
-#else
-    internal
-#endif  
-        class ChangeFeedItem<T>
+    public class ChangeFeedItem<T>
     {
         /// <summary>
         /// The current version of the item for all versions and deletes change feed mode.

Microsoft.Azure.Cosmos/src/Resource/FullFidelity/ChangeFeedMetadata.cs

@@ -15,12 +15,7 @@ namespace Microsoft.Azure.Cosmos
     /// <summary>
     /// The metadata of a change feed resource with <see cref="ChangeFeedMode"/> is initialized to <see cref="ChangeFeedMode.AllVersionsAndDeletes"/>.
     /// </summary>
-#if PREVIEW
-    public
-#else
-    internal
-#endif
-    class ChangeFeedMetadata
+    public class ChangeFeedMetadata
     {
         private readonly static DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
 

Microsoft.Azure.Cosmos/src/Resource/FullFidelity/ChangeFeedOperationType.cs

@@ -9,12 +9,7 @@ namespace Microsoft.Azure.Cosmos
     /// <summary>
     /// The operation type of a change feed resource with <see cref="ChangeFeedMode"/> is initialized to <see cref="ChangeFeedMode.AllVersionsAndDeletes"/>. Upsert operations will yield <see cref="Create"/> or <see cref="Replace"/>.
     /// </summary>
-#if PREVIEW
-    public
-#else
-    internal
-#endif 
-    enum ChangeFeedOperationType
+    public enum ChangeFeedOperationType
     {
         /// <summary>
         /// The create operation type.

Microsoft.Azure.Cosmos/src/Resource/Settings/ChangeFeedPolicy.cs

@@ -31,12 +31,7 @@ namespace Microsoft.Azure.Cosmos
     /// </code>
     /// </example>
     /// <seealso cref="ContainerProperties"/>
-#if PREVIEW
-    public
-#else
-    internal
-#endif
-    sealed class ChangeFeedPolicy
+    public sealed class ChangeFeedPolicy
     {
         [JsonProperty(PropertyName = Constants.Properties.LogRetentionDuration)]
         private int retentionDurationInMinutes = 0;

Microsoft.Azure.Cosmos/src/Resource/Settings/ContainerProperties.cs

@@ -379,12 +379,7 @@ public FullTextPolicy FullTextPolicy
         /// The change feed policy associated with the container.
         /// </value>
         [JsonIgnore]
-#if PREVIEW
-        public
-#else
-        internal
-#endif
-        ChangeFeedPolicy ChangeFeedPolicy
+        public ChangeFeedPolicy ChangeFeedPolicy
         {
             get
             {