nixos/frigate: fix recording and serving of clips/recordings

Frigate does string prefix matching for paths, which isn't exactly
compatible with dynamically provisioned directories of systemd, where
/var/cache/frigate is actually a symlink to /var/cache/private/frigate.

Because we are unlikely to get this fixed upstream, this is one of the
reason we should stop using DynamicUser= here.

The other being, that nginx needs to be able to serve clips and
recordings from both the CacheDirectory and the StateDirectory, and
nginx being a member on a group that may only exist after it was started
up doesn't work reliably.

This is also why we relax the umask to allow g+r/g+rx for newly created
files. Existing installs may need the following permissions fix to get
things going.

```
find /var/lib/frigate/recordings -type d -exec chmod g+rx {} \;
find /var/lib/frigate/recordings -type f -exec chmod g+r {} \;
find /var/cache/frigate -type f -exec chmod g+r {} \;
```

Co-Authored-By: Daniel Barlow <dan@telent.net>

0 files changed, 0 insertions, 0 deletions