[feature] show uploaded files size in conan upload

[leha-bot]

It would be very convenient to provide the size of files which will be upload to specific remote via conan upload ... in diagnostic purposes, e.g. sometimes artifacts could be very large and CI could refuse its uploading, see e.g. this StackOverflow question as example of related CI error. With this change CI administrators could adjust the file limit at CI without trial and error changing of CI configs.

• I've read the CONTRIBUTING guide.

[memsharded]

It is relatively straightforward to just check the files in the Conan cache in case the upload failed, so not a high priority. We might add it to the output in Conan 2.0, depends on how cluttered the output looks, might be added or not, we will see.

[mkmkme]

@memsharded was the decision to add it or to not? Should this ticket be closed?

[memsharded]

Neither, a decision was not taken. This kind of small ux details haven't been considered yet. I am fine with adding the info before/during upload of big files only (all files would be very noisy)