🧪 [testing improvement] Add missing tests for Status string representation

[adcondev]

🎯 What: Adding missing tests for Status.String() method in internal/service/status.go.
📊 Coverage: A table-driven test TestStatus_String now covers all the possible string representations of a service status: StatusStopPending, StatusStartPending, StatusRunning, StatusStopped, StatusNotInstalled, StatusUnknown, and an extra test for an undefined default case to verify the default fallback functionality.
✨ Result: 100% test coverage for the Status.String() functionality, making the codebase more robust against regressions.

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PR created automatically by Jules for task 7548648923162610710 started by @adcondev

[google-labs-jules]

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[github-actions]

⚡ Benchmark Results

⚠️ No benchmarks found in the current codebase.

To add benchmarks, create functions starting with Benchmark in *_test.go files.