Error handling has been reworked to always go through the new `error_template`,
`error_json` and `error_atom` macros.
They all accept a status code followed by a string message or an exception
object. `error_json` accepts a hash with additional fields as third argument.
If the second argument is an exception a backtrace will be printed, if it is a
string only the string is printed. Since up till now only the exception message
was printed a new `InfoException` class was added for situations where no
backtrace is intended but a string cannot be used.
`error_template` with a string message automatically localizes the message.
Missing error translations have been collected in https://github.com/iv-org/invidious/issues/1497
`error_json` with a string message does not localize the message. This is the
same as previous behavior. If translations are desired for `error_json` they
can be added easily but those error messages have not been collected yet.
Uncaught exceptions previously only printed a generic message ("Looks like
you've found a bug in Invidious. [...]"). They still print that message
but now also include a backtrace.
Using sudo with `echo ... | tee /path/to/file` doesn't make sense, as the command requiring the superuser privileges is the `tee` command and not the echo.
Now that themes are controlled with a class instead of setting
media="none" on the stylesheet link and both themes already being
duplicated in default.css for the automatic themeing it makes sense
to have all theme related CSS in the same place.
This commit also fixes the missing dark theme on embeds.
Themes are now controlled with a class on the body element.
If a preference is set the body element will have either "dark-theme"
or "light-theme" class. If no preference is set or the preference is
empty the class will be "no-theme".
"dark-theme" and "light-theme" are handled by darktheme.css and
lighttheme.css respectively.
"no-theme" is handled by default.css where depending on the value of
"prefers-color-scheme" the styles corresponding to "dark-theme" or
"light-theme" are applied.
Unfortunately this means that both themes are duplicated, once in the
theme .css and once in default.css.
