SharpPack 1.0.3

Performance and resource control

• Bound Context-dependent array, list, tuple and generated-object formatters
  once per Context, so steady-state serialization uses the selected formatter
  directly instead of repeatedly walking the formatter graph.
• Added exact-size byte[] serialization for eligible generated object types,
  avoiding the intermediate-buffer-to-result copy while preserving the
  MemoryPack wire format.
• Added configurable retained serializer buffers. The default is an unpinned
  8 KB buffer per active serializer thread, the high-throughput preset is an
  unpinned 80 KB buffer, and applications can choose any size from 1 through
  Array.MaxLength.
• Preserved the zero-allocation serializer hot path for pre-sized
  IBufferWriter<byte> destinations.
• Added reproducible NuGet-only BenchmarkDotNet comparisons against
  MemoryPack 1.21.4, including latency, throughput and allocation results.

Fixes for inherited MemoryPack issues

• Fixed generated unmanaged structs ignoring member-level custom formatters.
  MemoryPack's raw-copy path bypassed [MemoryPackCustomFormatter]; SharpPack
  now honors [SharpPackCustomFormatter] at the root and through arrays,
  lists, nullable values, tuples, key/value pairs, multidimensional arrays,
  closed generic shapes and generated object graphs. Plain unmanaged types
  keep the original raw-copy wire format and performance.
• Fixed truncated unmanaged-list payloads mutating an existing destination
  list before the payload byte count was validated. Both contiguous and
  segmented inputs now fail before changing caller-owned collection state.
• Fixed generated code for nested models losing required containing-type
  modifiers and generic constraints. Nested models inside static,
  readonly, ref and constrained generic partial types now compile with the
  correct containing declarations.

Correctness and compatibility

• Fixed formatter-factory method-name and return-type collisions, recursive
  Context factory construction, helper-name collisions and conditional generic
  policy classification without falling back to process-wide formatter state.
• Fixed nullable unmanaged List<T?> formatter selection and preserved custom
  element formatter composition for explicit array formatters.
• Added validation for custom retained-buffer sizes, exact writer bounds and
  malformed or truncated bulk collection payloads.
• Verified all 203 original-HEAD golden corpus entries in both directions,
  including byte-for-byte equality for deterministic payloads. No wire-format
  change is introduced by this release.