BUG: `ilamb debug` needs rework post logging changes

[nocollier]

Previously, the existence of a log file meant that something had gone wrong in the ilamb run. However, as now we provide additional logging which shows the users what steps were taken, many files may exist that simply have information in them.

• Revisit what ilamb debug does and see if we have any better ideas. At the moment it provides you a short overview of the exceptions that were raised.
• Log files do not append and so if you are working on a run that requires multiple executions to get right, you will lose the information about what we did and in place simply see a "using cached information". This should also be rethought. It should probably be an append but perhaps with some clear page break characters to help users see the separate runs.