[C#] Implement missing APIs

[yuslepukhin]

This pull request adds new APIs and updates existing ones to improve memory and device information handling in the ONNX Runtime C# bindings. The most significant changes introduce methods for fetching memory info and device info for session inputs/outputs, and add support for shared allocators and synchronization streams. There are also several updates and renamings for LoraAdapter delegates and related APIs.

Memory and Device Info APIs

• Added GetMemoryInfosForInputs, GetMemoryInfosForOutputs, and GetEpDeviceForInputs methods to InferenceSession.shared.cs to fetch memory info and device info for session inputs/outputs. These methods utilize new native delegates for retrieving memory and device information.
• Introduced native delegates in NativeMethods.shared.cs for OrtSessionGetMemoryInfoForInputs, OrtSessionGetMemoryInfoForOutputs, and OrtSessionGetEpDeviceForInputs, and wired them up in the static constructor. [1] [2]

Shared Allocator and Synchronization Stream Support

• Added delegates and static fields for creating, getting, and releasing shared allocators, as well as for creating and managing synchronization streams (OrtCreateSharedAllocator, OrtGetSharedAllocator, OrtReleaseSharedAllocator, OrtCreateSyncStreamForEpDevice, OrtSyncStream_GetHandle, OrtReleaseSyncStream).
• Added delegate for copying tensors (OrtCopyTensors).

LoraAdapter API Updates

• Renamed LoraAdapter-related delegates to use the Ort prefix (OrtCreateLoraAdapter, OrtCreateLoraAdapterFromArray, OrtReleaseLoraAdapter) and updated their usage throughout the codebase. [1] [2] [3]

MemoryInfo Enhancements

• Added new delegates for creating memory info with more parameters (OrtCreateMemoryInfoV2), and for querying device memory type and vendor ID (OrtMemoryInfoGetDeviceMemType, OrtMemoryInfoGetVendorId). [1] [2] [3]

Minor API Documentation Update

• Clarified the lifetime of allocators in the documentation, noting they can be explicitly unregistered.### Description

Motivation and Context

[Copilot]

Pull Request Overview

This pull request implements missing ONNX Runtime C# APIs to enhance memory management, device information handling, and synchronization capabilities. The changes focus on providing developers with better control over memory allocation and device-specific operations in ONNX Runtime C# bindings.

Key changes include:

• Added memory and device info retrieval methods for session inputs/outputs
• Introduced shared allocator management APIs with creation, retrieval, and release capabilities
• Implemented synchronization stream support for async operations and tensor copying
• Updated LoraAdapter APIs with consistent naming conventions

Reviewed Changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
csharp/src/Microsoft.ML.OnnxRuntime/NativeMethods.shared.cs	Added native delegates for memory info, shared allocators, sync streams, and tensor copying APIs
csharp/src/Microsoft.ML.OnnxRuntime/InferenceSession.shared.cs	Implemented session methods to retrieve memory info and device info for inputs/outputs
csharp/src/Microsoft.ML.OnnxRuntime/OrtEnv.shared.cs	Added shared allocator management and tensor copying functionality
csharp/src/Microsoft.ML.OnnxRuntime/OrtEpDevice.shared.cs	Added OrtSyncStream class and device memory info retrieval methods
csharp/src/Microsoft.ML.OnnxRuntime/OrtAllocator.shared.cs	Enhanced OrtMemoryInfo with new device memory types and V2 constructor
csharp/test/Microsoft.ML.OnnxRuntime.Tests.Common/OrtEnvTests.cs	Added comprehensive tests for shared allocator APIs and tensor copying
csharp/test/Microsoft.ML.OnnxRuntime.Tests.NetCoreApp/InferenceTest.netcore.cs	Added tests for new session memory info retrieval methods
csharp/test/Microsoft.ML.OnnxRuntime.Tests.Common/InferenceTest.cs	Updated memory info tests and moved shared allocator tests to OrtEnvTests

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[snnn]

This PR has been cherry-picked into the rel-1.23.1 branch in PR #26182. Removing the release:1.23.1 label.