Function escape_command_for_shell 

pub fn escape_command_for_shell(command: &str) -> String

Escape a command for safe execution in shell (for pkill -f patterns)

This escapes characters that could cause shell injection when used inside single-quoted shell strings (like in pkill -f 'command').

Escaped characters:

• Single quotes: ' → '"'"'
• Dollar signs: $ → \$ (prevents variable expansion)
• Backticks: ` → ``` (prevents command substitution)
• Backslashes: \ → \\ (prevents escape sequences)
• Parentheses: ( and ) → \( and \) (prevents subshells)
• Pipes: | → \| (prevents command chaining)

Example

use ssh_mcp::ssh::sanitize::escape_command_for_shell;

let escaped = escape_command_for_shell("echo 'hello' | cat");
assert_eq!(escaped, "echo '\"'\"'hello'\"'\"' \\| cat");