add command line switch to select dates to use

[anuaimi]

right now the dates for the planner pages are a variable in the code. It should be possible for a user to run the script with command line switches to set which dates to print planner pages for

[anuaimi]

consider using Commander

a lengthy tutorial but probably has enough to get core ideas https://blog.logrocket.com/building-typescript-cli-node-js-commander/

[anuaimi]

• if the script is run with no arguments, it should print out a pdf with pages for the current month. If the current date is after the 15th, it should print out pages for the next month
• there should be a switch to set the start date( --start-date 2023-03-01). The date must be in the format of yyyy-mm-dd.
• there should be a switch to specify how many months you want to generate pages for (-m, --months )
• there should be an option to specify whether printing on single-sided pages or double sided (--single-sided, -s or --double-sided -d). They should default to single sided. A user should not be able to specify both options unless they agree with each other