s/player_setrate/player_setup when the function was renamed, the error messages weren't.

use a strictier pledge for `amused add' now that we're using canonpath instead of realpath(3), we can drop the rpath pledge promise.

use canonpath instead of realpath(3) so we get the same behaviour with `add' and `load'

use canonpath (from kern_pledge.c) instead of home grow "equivalent"

drop unnecessary temp variable in main_restart_track

fmt; fold long lines

use getprogname(3) instead of __progname might help with portability, see for e.g. GitHub issue #1

avoid unnecessary initialization we're just gonna memcpy all over path again a couple of lines before; a smart compiler will probably ignore the initialization anyway.

free the imsg in player after handling, plugs a memory leak

inline player_enqueue

s/audio_init/player_init was the only function to disrespect the player_* namespace (well, excepting play). while here also don't mark those two as static, they were the only static functions in the file. I'm not trying to enforcing private symbols here.

no need to sio_setpar during initialization we don't know what format the music will be so we have to stop and set the parameters in player_setup. there's no point in setting bogus parameter in audio_init.

drop a local variable don't need to keep `files' around, res->files is enough. it would have prevented the previous bug (probably.)

fix `amused add' failure introduced in previous commit don't advance the files pointer, we need the original pointer when receiving the replies.

refactor: group imsg handling the approach with one-function-per-imsg leads to too much code splatted across the file.