fix: vim.uv usage, fixed deprecations, annotations

[DrKJeff16]

Changes

• Consistently used vim.uv, set vim.loop as fallback
• Massively reworked some colored_printer.lua sections
• Fixed deprecated calls in colored_printer.lua (NEEDS CHECK b092736)
• Annotations and documentation added/fixed
• Some other minor fixes

Note

Tests pass successfully

[quolpr]

@DrKJeff16 hey! Thanks for contribution! When I run abc_test.go from test dir, I get this error

Error in async job: ...w/Cellar/neovim/0.11.0/share/nvim/runtime/lua/vim/hl.lua:129: Invalid 'ns_id': -1
Stack trace: stack traceback:
        ...ojects/DrKJeff16/quicktest.nvim/lua/quicktest/module.lua:334: in function <...ojects/DrKJeff16/quicktest.nvim/lua/quicktest/module.lua:332>
        [C]: in function 'nvim_buf_set_extmark'
        ...w/Cellar/neovim/0.11.0/share/nvim/runtime/lua/vim/hl.lua:129: in function 'range'
        ...KJeff16/quicktest.nvim/lua/quicktest/colored_printer.lua:437: in function 'set_next_lines'

It's coming from here:

vim.hl.range(buf, -1, h.group, { lines_count -1 + i, h.start }, { lines_count -1 + i, h.end_ })

Also, TestGradient from abc_test.go stoped working(no gradient is printing)

[DrKJeff16]

vim.hl.range(buf, -1, h.group, { lines_count -1 + i, h.start }, { lines_count -1 + i, h.end_ })

@quolpr Thanks for the heads-up. That -1 is the issue there. Do I create a namespace? Do I use the global one (0)? Or is there a namespace I can use for it?