CI: add automated sound playback integration test

[Cuda-Chen]

• Create .ci/test-sound.sh to validate playback on host OS via expect.
• Integrate sound test into Ubuntu and macOS GitHub workflows.
• Set higher timeout for macOS (900s) to account for slower CI runners.

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Summary by cubic

Add virtio-snd CI to automatically validate sound playback in semu on Linux and macOS, catching audio regressions early.

• New Features
  • Added .ci/test-sound.sh that boots buildroot, logs in, plays ALSA sample via aplay, and checks for “Mono” output using expect.
  • OS-specific timeouts (30s Linux, 900s macOS) and pre-test cleanup.
  • Integrated the sound test into GitHub Actions for Ubuntu (5 min) and macOS (20 min) workflows.

^{Written for commit 1ba71a0. Summary will update automatically on new commits.}

[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name=".ci/test-sound.sh">

<violation number="1" location=".ci/test-sound.sh:27">
P1: Unreachable error handling code. The `ASSERT` function from `common.sh` exits the script directly on failure, so `ret=&quot;$?&quot;` and the subsequent `MESSAGES` array logic will never execute for error cases. The descriptive error messages (&#39;Fail to boot&#39;, &#39;Fail to login&#39;, etc.) will never be displayed.

Consider capturing the exit code without using ASSERT, or modify `test_sound` to not use ASSERT for this case.</violation>
</file>

_{Reply to cubic to teach it or ask questions. Tag @cubic-dev-ai to re-run a review.}

[jserv]

Improve descriptions about this pull request.

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name=".ci/test-sound.sh">

<violation number="1" location=".ci/test-sound.sh:43">
P1: `ret=&quot;$?&quot;` now captures the exit code of `echo` (always 0) instead of `test_sound`. This breaks the error message handling logic below. The success message should be printed after capturing the return code.</violation>
</file>

_{Reply to cubic to teach it or ask questions. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name=".ci/test-sound.sh">

<violation number="1" location=".ci/test-sound.sh:27">
P2: Using `ASSERT` here makes the error handling code below unreachable. When `expect` returns a non-zero exit code (1-4), `ASSERT` will immediately exit the script with a generic &quot;Assert failed: expect&quot; message, bypassing the specific error messages in the MESSAGES array. Either remove `ASSERT` to preserve the detailed error messages, or remove the now-dead MESSAGES handling code.</violation>
</file>

_{Reply to cubic to teach it or ask questions. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name=".ci/test-sound.sh">

<violation number="1" location=".ci/test-sound.sh:27">
P1: Removing `ASSERT` breaks error handling. Since the script uses `set -euo pipefail`, when `expect` fails, the script will exit immediately before `ret=&quot;$?&quot;` can capture the exit status. The error message logic (`MESSAGES` array) becomes dead code and users won&#39;t see helpful failure diagnostics. Other CI scripts (`test-netdev.sh`, `autorun.sh`) correctly use `ASSERT expect`.</violation>
</file>

_{Reply to cubic to teach it or ask questions. Tag @cubic-dev-ai to re-run a review.}

[jserv]

Improve git commit messages.

[jserv]

Improve git commit messages!

[jserv]

Thank @Cuda-Chen for contributing!