Improved Bash Command Safety Analysis

The Bash command safety checker now correctly parses command wrappers that prepend the real command, preventing false safety denials when using common Unix utilities:

• timeout — parses --foreground, --kill-after, --preserve-status, --signal, and duration arguments
• stdbuf — parses -i, -o, -e buffer-mode flags
• env — parses environment variable assignments and -i, -0, -u, -v flags
• time, nohup, nice — unwrapped to find the actual command being run
• These wrappers are recursively stripped before analyzing the inner command for safety