Improve debug experience

[wolfv]

It would be cool to improve the debug experience:

• rattler-build debug shell: should launch a shell like pixi shell in the work directory of the last build (or maybe show you a drop-down to select the thing you want to debug).
• rattler-build debug sync: inside the debug shell, should sync to the recipe state ie. add/remove dependencies, refresh or add sources if necessary (the recipe location could be derived from the PWD/work dir that we would need to associate with the output, or by adding a env var in the "debug shell"). We would also ideally store the "variant" that was chosen for the current build and the recipe invocation so that we can perform the sync and select the correct output & variant.
• rattler-build debug edit: open recipe to edit with $EDITOR
• the rattler-build create-patch function needs some bugfixing, specifically with sources that come with a Content-Disposition header as we currently store a wrong source location in our source info struct.