Erase FOTA image

[DennisMoschina]

added function to erase fota images

[DennisMoschina]

I created a fork of the mcumgr_flutter library to expose the erase function and opened a PR for it. We can't release this as a feature as long as this PR is not merged and released, as we can't release a package with a dependency to a git repository.

[github-actions]

Visit the preview URL for this PR (updated for commit 37df9d0):

https://open-earable-lib-web-example--pr128-feat-erase-image-nbxt4izc.web.app

_{(expires Mon, 15 Jun 2026 08:05:41 GMT)}

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