fix: prevent indefinite blocking in IPC handshake (#405)

[Aditya-Pan-pro]

Description

This PR implements enforced timeouts and atomic I/O operations for the IPC handshake.

• Asymmetric Deadlines: Added a 10s timeout for the listener (AwaitMessage) and a 5s backoff/retry loop for the client (SendIPCMessage) to prevent the runtime from hanging indefinitely.
• Atomic Messaging: Integrated io.ReadFull to ensure complete message delivery and prevent partial-read bugs.
• Error Clarity: Added explicit checks for net.Error timeouts to provide clear logging during failures.

Related issues

• Fixes IPC handshake can block indefinitely during container startup #405

How was this tested?

Manual testing was performed on Linux Mint 22.2 using custom Go test scripts and netcat:

• Listener Timeout: Verified AwaitMessage triggers a timeout after 10s when no connection is received.
• Client Timeout: Verified SendIPCMessage retries for 5s and fails when the socket is unavailable.
• Success Path: Verified a successful handshake by sending an "INIT" message via netcat, confirming io.ReadFull works as intended.

Note

I do not have the full e2e environment set up locally, so I am relying on the CI for the final integration check.

LLM usage

Assisted by Gemini 3 Flash for logic refinement, structuring the testing methodology, and drafting the technical documentation/PR description. All code was manually verified and tested locally.

Checklist

• I have read the contribution guide.
• The linter passes locally (make lint).
• The e2e tests of at least one tool pass locally (make test_ctr, make test_nerdctl, make test_docker, make test_crictl).
• If LLMs were used: I have read the llm policy.

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[cmainas]

The #405 issue has not been verified. Please do not open PRs for issues that have not been verified.

[Aditya-Pan-pro]

Sorry for submitting the code before the issue was officially approved. I will hold off on this PR for now. Please let me know if there are any logs or reproduction steps I can provide in issue #405 to help get it verified!