Weak guarantees for `IO#write` override

[itarato]

During CI bug investigation we noticed this code:

cli-ui/lib/cli/ui/stdout_router.rb

Lines 402 to 410 in f6294ff

	def activate(stream, streamname)
	writer = StdoutRouter::Writer.new(stream, streamname)
	raise if stream.respond_to?(WRITE_WITHOUT_CLI_UI)
	stream.singleton_class.send(:alias_method, WRITE_WITHOUT_CLI_UI, :write)
	stream.define_singleton_method(:write) do |*args|
	writer.write(*args)
	end

overriding IO#write for STDOUT and STDERR. This is quietly disabled by any call on IO#reopen, for example: a test calling #capture from https://github.com/rails/rails/blob/0e99d0893b0e98c626a3c7d8972eea22d29c9d25/activesupport/lib/active_support/testing/stream.rb#L23-L38

If the goal of the cli-ui code to be permanent, it needs adjustments. This is true for CRuby and TruffleRuby engines.

More details: truffleruby/truffleruby#3088