[TEST] Improve coverage and robustness for safeListSources and safeListTasks

[n24q02m]

Improved unit tests for safeListSources and safeListTasks in background.js.

• Added verification that callBatchExecute is called with correct RPC IDs ('YqkSHd' for sources, 'p1Takd' for tasks) and payloads.
• Used JSON.stringify for robust comparison of arrays returned from the node:vm sandbox to prevent realm mismatch issues.
• Added a new test case for safeListSources to verify that it correctly filters out non-GitHub sources and repos with Suggestions disabled.
• Isolated safeList wrapper testing by mocking internal functions (listTasks, listSuggestionEnabledSources) to verify error logging and recovery.

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PR created automatically by Jules for task 10275601429116819841 started by @n24q02m

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[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

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