Feat: use vim.diagnostic.status if available

[aktau]

Requested feature

Neovim just merged neovim/neovim#33723. The vim.diagnostic.status() function m ay be useful. It seems to render the same way as the current nvim_diagnostic, though that appears to be more flexible:

lualine.nvim/lua/lualine/components/diagnostics/sources.lua

Lines 35 to 56 in a94fc68

	nvim_diagnostic = function()
	local count
	if vim.diagnostic.count ~= nil then -- neovim >= 0.10.0
	count = vim.diagnostic.count(0)
	return count[vim.diagnostic.severity.ERROR] or 0,
	count[vim.diagnostic.severity.WARN] or 0,
	count[vim.diagnostic.severity.INFO] or 0,
	count[vim.diagnostic.severity.HINT] or 0
	end
	-- fallback
	local diagnostics = vim.diagnostic.get(0)
	count = { 0, 0, 0, 0 }
	for _, diagnostic in ipairs(diagnostics) do
	count[diagnostic.severity] = count[diagnostic.severity] + 1
	end
	return count[vim.diagnostic.severity.ERROR],
	count[vim.diagnostic.severity.WARN],
	count[vim.diagnostic.severity.INFO],
	count[vim.diagnostic.severity.HINT]
	end,

.

Also interesting is that this change seems to force/issue a redraw command when diagnostics change. If lualine also registers that, it would improve performance to no longer do it.

Motivation

It may simplify code.