A minimal and portablel vi configuration, to make CLI a little more usable. Additionally there are some comments at the bottom as reminders of important vi key bindings.

.vimrc

""" A minimal, portable vi configuration, use in ~/.exrc or ~/.vimrc """
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function! ResetOsTheme()
  " Detect current macOS theme
  let l:os_theme = system("defaults read -g AppleInterfaceStyle 2> /dev/null")

  " Adjust Vim settings based on macOS theme
  if l:os_theme == "Dark\n"
    " Set Vim to dark theme settings
    set background=dark
    highlight Comment ctermfg=Gray
    highlight Constant ctermfg=Blue
    highlight Normal ctermfg=White
    highlight NonText ctermfg=White
    highlight Special ctermfg=DarkMagenta
    highlight Cursor ctermfg=Green
    highlight LineNr ctermfg=DarkGray
    highlight Search ctermfg=White ctermbg=Blue
  else
    " Set Vim to light theme settings
    set background=light
    highlight Comment ctermfg=DarkGray
    highlight Constant ctermfg=DarkBlue
    highlight Normal ctermfg=Black
    highlight NonText ctermfg=Black
    highlight Special ctermfg=DarkMagenta
    highlight Cursor ctermfg=Green
    highlight LineNr ctermfg=Gray
    highlight Search ctermfg=Black ctermbg=Yellow
  endif
endfunction

" Compatibility, run with -u to override
if &compatible
  set nocompatible
endif

" Try to identify the indenation of file type for use
if has('filetype')
	filetype plugin indent on
endif

" Enable syntax highlighting if available for file type
if has('syntax')
	syntax on
endif

" Customize visual appearance based on OS theme
call ResetOsTheme()
set hlsearch

" Status and command line bar adjustments
set wildmenu
set showcmd
set cmdheight=2
set laststatus=2

" Faster mode timeouts
set notimeout ttimeout ttimeoutlen=200

" Case insensitive search
set ignorecase
set smartcase

" Confirmation dialog
set confirm

" Additional tab, spacing and indentation behavior
set tabstop=4
set shiftwidth=4
set softtabstop=4
set expandtab
set autoindent
set backspace=indent,eol,start


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""" Additional features and usability tweaks
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" Show which mode vi is in
set showmode

" Show cursor position
set ruler

" Show line numbers
set number

" Don't jump to the start of the line when switching lines
set nostartofline

" Use mouse navigation, if available 
if has('mouse')
  set mouse=a
endif

" Use visual bell instead of chime for errors
set visualbell



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""" Useful vim syntax reminders
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" hjkl = arrows for original qwerty keyboard that didn't have arrow keys

" 0 = start of line
" $ = end of line

" w = next word
" b = preceding word
" (Using the keyboard arrow keys in conjunction with the shift key may also do this)

" ^u = Up half screen
" ^d = Down half screen

" :0 = first line
" :n = nth line
" :$ = last line

" i = insert at cursor
" A = end of line
" I = insert start of line

" u = toggle undo

" x = delete single char
" D = delete rest of line
" dd = delete line
" ndd = delete n lines

" yy = yank line (copy)
" P = paste
" nyy = yank n lines

" /foo = search foo
" ?foo = search backwards
" n = next result
" N = previous result

" ^g = line count