The question of saving a copy of software in public cloud is probably moot, however this is almost certainly legal provided it is not used to distribute the software. (I understand a public cloud to be cloud resources which are off-premise and owned by someone else, but under your control - which is distinct from making something available to anyone)
The relevant question is one of licensing - and provided you have the right to distribute the software to users you limit your distribution if required under your license this is legal. If the software you are using is licensed, "making available" is most likely a breach of laws - which may vary from place to place in their specifics and enforcement - but are, nonetheless likely to be a breach.
In the case of Taiwan, I expect this is covered by the Copyright Act (as per Laws & Regulations Database of the Republic of China) - specifically clause 10
"10.Public transmission" means to make available or communicate to
the public the content of a work through sounds or images by wire or
wireless network, or through other means of communication, including
enabling the public to receive the content of such work by any of the
above means at a time or place individually chosen by them."
combined with Article 26-1 which states
Except as otherwise provided in this Act, authors of works have the
exclusive right of public transmission of their works. Performers have
the exclusive right of public transmission of their performances
reproduced in sound recordings.
That said, Arduino IDE can be freely distributed as its licensed under the GPL which is designed to specicially to allow free distribution - specifically the preambe of the GPL Version 2 (which this software uses) states
" Our General Public Licenses are designed to make sure that you have
the freedom to distribute copies of free software (and charge for this
service if you wish), that you receive source code or can get it if
you want it, that you can change the software or use pieces of it in
new free programs; and that you know you can do these things. "