Displays the current month with the current day highlighted. Similar to cal, ncal, etc.

The calendar can be navigated interactively.

Can also show three months at a time (flag --three).

• implement a 3-month view which includes the month names on the left (as shown the example below).
• provide a flag for colorless output.
• do major refactor and clean up complicated function signatures.
• remove all ansii after every printed line in order to make embeddable into other projects.
• make calendar pipeable
  • eg. selectedDate=$(neocal)
  • eg. neocal | (read x; echo "$x")
• give option flag to restrict selection to a list of date ranges.
  • eg. -restrict '2022-01-01=2022-02-01,2020-01-01=2020-02-01' only allows selections in Jan 2020 or 2022.
• auto-update GUI when next day came.

Later/maybe:

• tests for most extreme dates
  • test for negative years, eg year -1 (do not let user navigate into pre-historic past).
  • test for 5-digit years, eg year 10000 (do not let user navigate in post-historic future).
• have interactive events.
  • let user associated input forms with certain days of the calendar.
  • show interactive events on days (eg blue font highlight).
  • activate interactive events with special key (eg enter/space).
• have script events.
  • let user associated script with certain days of the calendar.
  • show script events on days (eg blue font highlight).
  • activate script events with special key (eg enter/space).
  • run the associated script.

The 3-month view could look something like this or similar:

Dec   1  2  3  4  5  6  7
      8  9 10 11 12 13 14
     15 16 17 18 19 20 21
     22 23 24 25 26 27 28
Jan  29 30 31  1  2  3  4
      5  6  7  8  9 10 11
     12 13 14 15 16 17 18
     19 20 21 22 23 24 25
Feb  26 27 28 29 30 31  1
      2  3  4  5  6  7  8
      9 10 11 12 13 14 15
     16 17 18 19 20 21 22

• add 3-month view
• make main return a date string (format: time.DateOnly, ie '2006-01-02').
• make the model navigable via vim home row keys (hjkl).
  • go to next month when leaving left or right.

For formatting bubbletea and lipgloss were used.