[Store] Add Pure C Interface of Client

[JINGE-ui]

1. This PR provides a C interface wrapper for mooncake-store. See client_c.h and client_c.cpp for details. After compiling Mooncake Store, you can use the static library file libmooncake_store.a and the C header file client_c.h for further development.

2. At present, client_c.h only wraps Client's key functions, such as Create, RegisterLocalMemory, MountSegment, Get, Put, IsExist, and Remove.

[stmatengss]

Thank you for your contributions! 1. Can you wrap more APIs (e.g., batch set/get) into C files? 2. It's recommended to add C-based end-to-end tests for CI testing.

[JINGE-ui]

Thank you, I will try

[JINGE-ui]

This PR builds on the previous submission by:

1. Correcting code formatting
2. Increasing the number of pure C API of mooncake::Client
3. Creating client_c_integration_test.cpp to test the C interfaces in client_c.h

[stmatengss]

Suggested change

	// types.h 中的 ErrorCode Code
	// ErrorCode Code in types.h

[stmatengss]

Suggested change

	// 管理 client 对象的生命周期
	// Managing the lifecycle of client objects

[stmatengss]

This PR builds on the previous submission by:

1. Correcting code formatting
2. Increasing the number of pure C API of mooncake::Client
3. Creating client_c_integration_test.cpp to test the C interfaces in client_c.h

1. Some client APIs, such as put/get_tensor and batch_get_into, which are used in SGLang, are not well-implemented.
2. Please ensure all comments are in English.

Thank you.

[stmatengss]

@JINGE-ui could you update this PR?

[stmatengss]

14: /home/runner/work/Mooncake/Mooncake/mooncake-store/tests/client_c_integration_test.cpp:91: Failure
14: Expected equality of these values:
14:   mount_result
14:     Which is: -900
14:   ((ErrorCode_t)0)
14:     Which is: 0
14: Failed to mount segment
14: [ RUN      ] ClientCIntegrationTest.BasicPutGetOperations
14: AddressSanitizer:DEADLYSIGNAL


14: /home/runner/work/Mooncake/Mooncake/mooncake-store/tests/client_c_integration_test.cpp:117: Failure
14: Expected equality of these values:
14:   test_client_mount_result
14:     Which is: -900
14:   ((ErrorCode_t)0)
14:     Which is: 0
14: Failed to mount segment for test_client_

Two test cases cannot pass in CI.