🧪 [Add test for std.http listen capability check]

[Tcode-Motion]

🎯 What: Added a missing test case to ensure the listen method in std.http correctly enforces the Network capability check.
📊 Coverage: The test suite now explicitly covers the error path when a script attempts to start an HTTP server without the Network capability, matching the existing coverage for get and post.
✨ Result: Increased test coverage and assurance that the security policy is uniformly enforced across all network operations without requiring an actual port bind during testing.

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PR created automatically by Jules for task 4767069077362948809 started by @Tcode-Motion

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