[LOADED_DOCS: 3 files, no new loads]

Rename ShallowCopy to FlatCopy, add polymorph support

- Renamed all "ShallowCopy" serializer presets and references to "FlatCopy" for clarity and consistency.
- Expanded documentation to clarify flat serialization use cases, especially for delta-update and partial-write scenarios.
- Added EnablePolymorphDetectFeature to AcBinarySerializableAttribute and updated all constructor overloads.
- Set UsePolymorphType = true in AcBinarySourceGenerator to enable polymorphic type support by default.
- Updated all [AcBinarySerializable(...)] usages to include new feature flags, explicitly disabling property filter and polymorph detection for affected types.
- Improved comments and documentation for maintainability.

AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs

@@ -43,7 +43,7 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
     // ────────────────────────────────────────────────────────────────────────────────────────────
     // UsePropertyFilter const removed — replaced by `[AcBinarySerializable(EnablePropertyFilterFeature = ...)]`
     // attribute flag, propagated through SerializableClassInfo.EnablePropertyFilter to EmitProp/EmitScanProp.
-    private const bool UsePolymorphType = false;
+    private const bool UsePolymorphType = true;
 
     private static readonly DiagnosticDescriptor CircularReferenceWarning = new(
         id: "ACBIN001",

AyCode.Core/Serializers/Attributes/AcBinarySerializableAttribute.cs

@@ -31,26 +31,22 @@ public sealed class AcBinarySerializableAttribute : Attribute
     /// per-property filtering for this specific type.</para>
     /// </summary>
     public bool EnablePropertyFilterFeature { get; }
+    public bool EnablePolymorphDetectFeature { get; }
 
     public AcBinarySerializableAttribute() : this(true)
     {
     }
 
-    public AcBinarySerializableAttribute(bool enableAllFeatures)
+    public AcBinarySerializableAttribute(bool enableAllFeatures) : this(enableAllFeatures, enableAllFeatures, enableAllFeatures, enableAllFeatures, enableAllFeatures, enableAllFeatures)
-    {
+    { }
-        EnableMetadataFeature = enableAllFeatures;
-        EnableIdTrackingFeature = enableAllFeatures;
-        EnableRefHandlingFeature = enableAllFeatures;
-        EnableInternStringFeature = enableAllFeatures;
-        EnablePropertyFilterFeature = enableAllFeatures;
-    }
 
-    public AcBinarySerializableAttribute(bool enableMetadataFeature, bool enableIdTrackingFeature, bool enableRefHandlingFeature, bool enableInternStringFeature, bool enablePropertyFilterFeature)
+    public AcBinarySerializableAttribute(bool enableMetadataFeature, bool enableIdTrackingFeature, bool enableRefHandlingFeature, bool enableInternStringFeature, bool enablePropertyFilterFeature, bool enablePolymorphDetectFeature)
     {
         EnableMetadataFeature = enableMetadataFeature;
         EnableIdTrackingFeature = enableIdTrackingFeature;
         EnableRefHandlingFeature = enableRefHandlingFeature;
         EnableInternStringFeature = enableInternStringFeature;
         EnablePropertyFilterFeature = enablePropertyFilterFeature;
+        EnablePolymorphDetectFeature = enablePolymorphDetectFeature;
     }
 }

AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs

@@ -34,10 +34,10 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     };
 
     /// <summary>
-    /// Options for shallow serialization (root level only).
+    /// Options for flat serialization (root level only).
     /// Returns a new instance each time to prevent shared state corruption.
     /// </summary>
-    public static AcBinarySerializerOptions ShallowCopy => new()
+    public static AcBinarySerializerOptions FlatCopy => new()
     {
         MaxDepth = 0,
         // Truncate preserves the original "root + Null nested" semantic; under default Throw the preset

AyCode.Core/Serializers/Binaries/README.md

@@ -93,7 +93,7 @@ Key wire-format options: `WireMode` (Compact/Fast), `ReferenceHandling` (None/On
 
 `ReferenceHandling=None` + `UseStringInterning=None` = no scan pass (single-phase, fastest).
 
-Presets: `Default`, `FastMode`, `ShallowCopy`, `WasmOptimized`. Details: `docs/BINARY/BINARY_OPTIONS.md`.
+Presets: `Default`, `FastMode`, `FlatCopy`, `WasmOptimized`. Details: `docs/BINARY/BINARY_OPTIONS.md`.
 
 ## Dependencies
 

AyCode.Core/Serializers/Jsons/AcJsonSerializerOptions.cs

@@ -16,10 +16,10 @@ public sealed class AcJsonSerializerOptions : AcSerializerOptions
     public static AcJsonSerializerOptions Default => new() { ReferenceHandling = ReferenceHandlingMode.All };
 
     /// <summary>
-    /// Options for shallow serialization (root level only, no references).
+    /// Options for flat serialization (root level only, no references).
     /// Returns a new instance each time to prevent shared state corruption.
     /// </summary>
-    public static AcJsonSerializerOptions ShallowCopy => new() { MaxDepth = 0, ReferenceHandling = ReferenceHandlingMode.None };
+    public static AcJsonSerializerOptions FlatCopy => new() { MaxDepth = 0, ReferenceHandling = ReferenceHandlingMode.None, MaxDepthBehavior = MaxDepthBehavior.Truncate};
 
     /// <summary>
     /// Creates options with specified max depth.

AyCode.Core/Serializers/Jsons/README.md

@@ -40,7 +40,7 @@ Custom JSON serialization/deserialization built on `System.Text.Json`'s `Utf8Jso
 | `MaxDepth` | Maximum object graph depth |
 | `ThrowOnCircularReference` | Throw vs silently handle circular refs |
 
-**Presets:** `Default` (with refs), `ShallowCopy`, `WithMaxDepth`, `WithoutReferenceHandling`.
+**Presets:** `Default` (with refs), `FlatCopy`, `WithMaxDepth`, `WithoutReferenceHandling`.
 
 ## Dependencies
 

AyCode.Core/docs/BINARY/BINARY_ISSUES.md

@@ -196,7 +196,7 @@ The shallow-serialization use case is a legitimate, common pattern (client edits
 - `Truncate` — the previous `WriteByte(Null)` behavior, now explicit opt-in for shallow serialization (delta updates, view-model projections, partial DB-update flows). The wire `Null` at the truncation boundary is the developer's contract decision — endpoint protocol dictates what nested null means. Works with any persistence layer (Dapper, ADO.NET, Cosmos DB, MongoDB, Redis, EF Core, etc.).
 - `Disable` — skip the depth check entirely (max perf, dev guarantees cycle-free graph).
 
-The check moved from "every object/collection write" (with rewind) to "before any marker byte is written" (in `WriteObject` runtime + `WriteObjectFullMarker*` SGen). The `ShallowCopy` preset was updated to explicitly set `MaxDepthBehavior = Truncate` to preserve its original "root + Null nested" semantic. See `BINARY_OPTIONS.md` `MaxDepth + MaxDepthBehavior` section for full details.
+The check moved from "every object/collection write" (with rewind) to "before any marker byte is written" (in `WriteObject` runtime + `WriteObjectFullMarker*` SGen). The `FlatCopy` preset was updated to explicitly set `MaxDepthBehavior = Truncate` to preserve its original "root + Null nested" semantic. See `BINARY_OPTIONS.md` `MaxDepth + MaxDepthBehavior` section for full details.
 
 ### ACCORE-BIN-I-W3F4: PropertyFilter + UseMetadata=false silently corrupts via index drift
 

AyCode.Core/docs/BINARY/BINARY_OPTIONS.md

@@ -146,14 +146,14 @@ delegate PropertyInfo? PropertyMapperDelegate(PropertyInfo sourceProperty, Type
 |--------|----------|----------|-----------------|-------------|----------|------------------|-------------|-------|
 | `Default` | Compact | false | Attribute | All | 255 | Throw | None | — |
 | `FastMode` | Compact | false | None | None | 255 | Throw | None | No scan pass |
-| `ShallowCopy` | Compact | false | None | None | **0** | **Truncate** ⚠️ | None | Root + Null nested (the Truncate behavior makes this preset's semantic meaningful — under default `Throw` it would throw on first nested object) |
+| `FlatCopy` | Compact | false | None | None | **0** | **Truncate** ⚠️ | None | Root + Null nested (the Truncate behavior makes this preset's semantic meaningful — under default `Throw` it would throw on first nested object) |
 | `WasmOptimized` | Compact | false | Attribute | All | 255 | Throw | None | +StringCaching |
 | `WithoutReferenceHandling` | Compact | false | Attribute | **None** | 255 | Throw | None | No scan pass |
 | `WithoutMetadata` | Compact | **false** | Attribute | All | 255 | Throw | None | — |
 
 **Performance implication of presets:**
 - `Default` / `WasmOptimized` — two-phase (scan + serialize) due to `ReferenceHandling=All`
-- `FastMode` / `ShallowCopy` — single-phase (no scan pass) since both interning and refs are disabled
+- `FastMode` / `FlatCopy` — single-phase (no scan pass) since both interning and refs are disabled
 - The scan pass adds ~20-30% overhead; disable it when the object graph is a simple tree
 
 ## Option Interactions