[$] The first half of the 6.7 merge window

As of this writing, 9,842 non-merge changesets have found their way intothe mainline repository since the 6.7 merge window opened. Nearly a thirdof those consist of the entire bcachefs development history but, evendiscounting that, there has been a lot of material landing for the nextrelease. Read on for a summary of the most interesting changes pulled sofar in this development cycle.