apt-cacher-ng: Package import stopped working

[David Wright <deblis@lionunicorn.co.uk>]

I installed trixie from scratch with the 13.2 netinst just over
two weeks ago, my second such installation. To save bandwidth,
I copied the trixie packages saved from my first installation
into /var/cache/apt/archives: it's now a 6.7GB .deb collection.
As this laptop runs pretty much 24/7, I decided to install
apt-cacher-ng on it, rather than my usual workaday desktop.

Following the acng guide, I attempted to import my packages,
and got the same symptoms as reported here at #5. The opening
words, "Since the update to 3.7.5-1," gave me hope, though;
so I carried out the following operations:

1. Re-moved the package collection out of /v/c/acng/_import/
   back into a safer location,

2. Removed apt-cacher-ng and its three dependencies that were
   recently installed (/only/ purging the dependencies), but
   see step 8,

3. Manually downloaded bookworm's version of apt-cacher-ng,

4: Attempted to install it, which required libc-ares2 in
   addition as a dependency,

5. Manually downloaded (trixie's) libc-ares2, and installed
   apt-cacher-ng and libc-ares2 together,

6. Moved the package collection back into /v/c/acng/_import/,

7. Import now worked.

I now have 5.2GB under debrep, and 1.7GB left behind in _import,
and the latter seems reasonable with there being 8 old chromiums,
4 old firefoxes, one old libreoffice suite and a linux-image
among the detritus. So,

8. apt-get upgrade   which upgraded apt-cacher-ng. I left
   libc-ares2 installed though it's currently redundant.
   (Removing the three dependencies at step 2 was unnecessary.
   Had this procedure not worked, I was going to remove acng
   for the time being, and use a USB stick instead.)

As this bug has been open for 17 months, I hope this post
might be of use to somebody.

Cheers,
David.