New upload algorithm and modified actions

[lukaskremla]

Added new upload algorithm logic for building target file paths and cleaned up existing methods.

Execute in REPL action is now only clickable for single non-directory file selections.

Upload action now uses the new upload algorithm and its description changes based on the current file/folder selection.

[lukaskremla]

Regarding the execute in REPL, in the old PRs we have at some point discussed whether the plugin should allow users to run non .py files in REPL.

You said that it should be possible, but I think that this functionality should be adjusted to only allow .py and .mpy files to be executed in REPL. Just like Windows won't let me execute an executable file if I change its extension from .exe to .txt this plugin shouldn't let people execute other files. I don't see a use case where I'd put a MicroPython script inside of a file with a .txt extension and then need to execute it in REPL.

As a user of this plugin it seems very reasonable that this plugin will only allow me to execute .py or .mpy files in REPL.

[elmot]

Now the PR is not compatible with the base branch and needs to be rebased

[lukaskremla]

Now the PR is not compatible with the base branch and needs to be rebased

Should be up to date again. I've modified the new upload algorithm to hopefully include all of the important changes you've made.

I have also added the extension check back as mentioned. I did the python file comparison the way you suggested before, but I believe that the mpy comparison can't be done similarly.

I think the check should be present as I have explained above, but ultimately this is up to you.