Standardizing an exposure classification for existing outputs (pre-BIP)

The latest version 0.4.0 of the software has been released, and can be accessed here. A significant update includes Appendix A, which introduces specific action keys for different levels: MIGRATE, SWEEP_WHEN_SPENDING, NONE, and TREAT_AS_MIGRATE. These keys are critical as they guide the user on the necessary actions to be taken at each level, with a clear demarcation provided by a "floor" below which the wallets have complete autonomy.

Additionally, there have been substantial revisions to both the Abstract and the Motivation sections of the document to present the reasoning behind these classifications more directly and clearly. This direct approach aims to enhance understanding and implementation efficiency. Feedback, particularly regarding the wording of the floor from the perspective of wallet operations, is solicited to ensure that the document remains relevant and accurate. Adjustments will be incorporated as needed to align with user feedback and operational realities.