feat(file): add new file utils

build: use install command

chore: use strict mode when compiling

feat(str): add s_concat_arr and fix s_concat

chore(io): namespace prefix all io fns

chore(io): add n_written param to write_all

chore: refactor to use size_t

feat(io): add write_all utility

feat(buffer): add buffer_slice util fn

build: fix erroneous test dep path in unit_test rule

docs: add doc comments for all allocator functions

fix(build): correct test dep filtering in Makefile

feat(array): add free fn to array_free

feat(io): add io utils, starting with read_all

chore: migrate test runner to exbotanical/libtap