🔒 Fix command injection vulnerability in process execution

[Tcode-Motion]

🎯 What: The vulnerability allowed an attacker with Capability::Process to pass arbitrary string input into Command::new(cmd) within the run and spawn functions, which could be exploited (e.g., executing shell interpreters) if the input was not properly sanitized.
⚠️ Risk: If an attacker can control the command being executed, they can run unintended processes or exploit underlying OS features, bypassing the intended safe confines of the language context despite capabilities being theoretically controlled.
🛡️ Solution: Added a security validation check in both run and spawn to strictly reject commands containing known shell metacharacters and spaces (&, |, ;, $, >, <, '', !, \n, \r, , \t`), mitigating the risk of executing complex command strings or unintended binaries while preserving intended functionality. Added a corresponding test case to verify protection.

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PR created automatically by Jules for task 394730116232511581 started by @Tcode-Motion

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