101 print a single normalized program when passed user defined rules

[deemp]

Closes #101

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PR-Codex overview

Detailed summary

• Added a new command-line option --single to print a single normalized program.
• Modified the behavior of printing the rule set title to only print it when --single is not specified.
• Updated the main function to handle the new --single option and print the single normalized program if specified.
• Added error handling for cases where the program cannot be normalized.
• Updated the output format to include step numbers when --chain is specified.
• Added new user instructions to the README.md file.

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