fix(multimodal): gate shm-namespace test to Linux

[slin1237]

Summary

The local_shm_namespace_id_resolves_on_linux test was gated with #[cfg(unix)], but it reads Linux-only paths (/proc/sys/kernel/random/boot_id and /dev/shm). On macOS dev hosts (which are also unix), the test fails because those paths don't exist.

Re-gated the test to #[cfg(target_os = "linux")] so it only runs on Linux where the required paths exist.

Test plan

• cargo build -p smg - clean
• cargo test -p smg --lib routers::grpc::multimodal - 19 passed, test correctly skipped on macOS
• cargo clippy -p smg --all-targets - clean (only pre-existing warnings)

CI (Linux) behavior unchanged - the test will continue to run and pass on Linux CI.

Summary by CodeRabbit

• Tests
  • Restricted a platform-specific test to run only on Linux, improving compatibility across other Unix-like environments.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: ac09a763-9538-4989-a55c-1a13918f4d2b

📥 Commits

Reviewing files that changed from the base of the PR and between 74f82cf and c732986.

📒 Files selected for processing (1)

• model_gateway/src/routers/grpc/multimodal.rs

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📝 Walkthrough

Walkthrough

The test module for local_shm_namespace_id_resolves_on_linux is now compiled only on Linux targets instead of all Unix targets.

Changes

Linux test gating

Layer / File(s)	Summary
Target OS gate change model_gateway/src/routers/grpc/multimodal.rs	The local_shm_namespace_id_resolves_on_linux test module now uses #[cfg(target_os = "linux")] instead of #[cfg(unix)].

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Poem

A bunny hopped through Linux snow,
Where one small test now learns to go.
Unix wide doors close, snug and bright,
target_os = "linux" feels just right.
🐇

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: restricting the shm-namespace test to Linux.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/shm-namespace-test-linux-gate

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_{Comment @coderabbitai help to get the list of available commands.}

[gemini-code-assist]

Code Review

This pull request updates the conditional compilation attribute for the local_shm_namespace_id_resolves_on_linux test in multimodal.rs from #[cfg(unix)] to #[cfg(target_os = "linux")] to ensure it only runs on Linux environments. There are no review comments to address, and I have no additional feedback to provide.

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[claude]

👋 The PR description doesn't fully follow PULL_REQUEST_TEMPLATE.md:

• Missing header: ## Description
• Missing header: ### Problem
• Missing header: ### Solution
• Missing header: ## Changes
• Missing header: ## Test Plan (present as ## Test plan — case mismatch)

Please update the PR description so reviewers have the context they need.

[claude]

Clean one-liner — the cfg gate now matches the paths the test actually reads. No issues found.