feat: allow drag and drop of image file in prompt textArea

[PhilKes]

This PR closes #554

Adds support for drag&drop of a single image file into the prompt

[PhilKes]

@carlrobertoh no idea why the ChatToolWindowTabPanelTest.testSendingOpenAIMessageWithImage fails, it succeeds locally.
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
https://github.com/carlrobertoh/CodeGPT/actions/runs/9112340838/job/25051402045?pr=566#step:4:724

[carlrobertoh]

Noice! 👍

It happens because the tests on the Github runner are executed in headless mode. You can replicate this by running export JAVA_TOOL_OPTIONS='-Djava.awt.headless=true' before executing the tests. Not sure what the fix is yet.

[PhilKes]

Noice! 👍

It happens because the tests on the Github runner are executed in headless mode. You can replicate this by running export JAVA_TOOL_OPTIONS='-Djava.awt.headless=true' before executing the tests. Not sure what the fix is yet.

Ah I see, in the DropTarget constructor:

public DropTarget(Component c, int ops, DropTargetListener dtl,   boolean act, FlavorMap fm)  throws HeadlessException   {
        if (GraphicsEnvironment.isHeadless()) {
            throw new HeadlessException();
        }
      ...
}

[carlrobertoh]

Hmm, apparently this results in null on macOS, or at least it doesn't work for me. 😞

Here's bit of a context: https://stackoverflow.com/a/64926775

I tried using the latest JB JRE while running the plugin locally, as suggested. I also installed the plugin manually on my actual IDE, but both scenarios resulted in a NPE. I haven't tried the first option yet tho.

[PhilKes]

Hm that is quite annoying. Unfortunately I do not have macOS so I can't try it out myself 🙃