feat: add accelerator daemon process wrapper

[mutianf]

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Fixes #<issue_number_goes_here> 🦕

[gemini-code-assist]

Code Review

This pull request introduces the AcceleratorDaemon class to manage the lifecycle of the Go accelerator daemon subprocess, including spawning the binary, waiting for its Unix domain socket (UDS) to become connectable, and handling teardown. The review feedback identifies several critical robustness and cross-platform compatibility issues: a potential file-locking issue on Windows when cleaning up after a failed spawn, platform-specific errors due to the direct use of socket.AF_UNIX and signal.SIGKILL (which are not supported on all platforms), and a missing cleanup step for self._log_path in _cleanup_tempdir.