chore: support build with glibc

fix: proper calloc arguments

chore: silence mkdir and rm in Makefile

feat: print usage on unrecognized input

release: 1.2.0

feat: add prompt command aliases

chore: use tcc instead of gcc

doc: TUI metronome -> metronome TUI

feat: display version with -v|--version

feat: support command-line args for editing files

perf: define wave constants as macros

fix: skip wave calculation on rests

- it worked previously with the sawtooth waves since freq=0 > inc=0 when
  there is a rest. the sine waves however has a vertical translation,
  causing the wave data to be at a constant value > 0, which introduced
  unwanted noises

test: null terminate forked output

chore: use gcc instead of clang

- increased error buffer size from +18 to +19 because gcc is not aware
  of the manual null termination and gives a false positive warning
  about overflow

chore mark (un)install rules .PHONY

chore: create install dest dirs if non-existent

chore: explicit destination for install

doc: add clang and scdoc as build deps

test: use local test directory

test: swap incorrect expected vs result order