Test for the 'no usable media' message
Inform when no usable media files are found (#103)
Point to the home page rather than the wiki on sourcehut
That broke when item_list became audio_list
Load custom css last, add tests for that and logo selection
Sometimes parts of file names or titles are big

Names were previously truncated if they were one big continuous
string, but parts of file names or titles can be really big too.  This
causes overflows on mobile, so those are now truncated as well.
Let the nav be one line on mobile
Theater View is 90%, not 100%
Fix theater mode

It broke when I changed what 'theme' is
Clean up style handling

Moved most if not all of the logic about what CSS is rendered into the
python backend.

Now, the only template-side logic is there to conditionally load the
dark theme when light is selected.

The "/css" part of the paths for each theme has been trimmed out and
is now explicit; the prefix is properly computed based on if debug is
True or not and "/css" is a part of that computation.
Point to the ticket, not the wiki
There are more than one now!
Clean up the settings page

Now it's a table layout with one submit button, using one form element
instead of two separate ones.