Migrates fs_read/write/exists/mkdir/write_bytes/list, exec/exec_bg/exec_command/exec_capture,
env/args/exit_program, state_set/get/del/keys, uuid_new/v4, and list helpers get/len from
el_runtime.c into El source as thin wrappers over seed primitives.
Introduces El's first-class threading primitives built on the seed layer's
__thread_create/__thread_join/mutex ops. parallel_map is the key deliverable:
spawns one thread per item, joins in order — replaces bash fan-out for room
dispatch and any other concurrent HTTP workload.
Thin El wrappers over seed JSON primitives (json_get, json_get_raw,
json_parse, json_stringify, json_set, json_array_len, json_array_get,
json_array_get_string) plus typed extractors (json_get_string/int/float/bool)
and pure-El builders (json_build_object, json_build_array,
json_escape_string) that require no seed call.
Thin El wrappers over seed primitives that form the public HTTP API for
El programs. Covers GET/POST/DELETE, header-map variants, binary streaming
to file, form-auth, v1/v2 server dispatch, and http_response envelope
construction. Documents two new seed primitives needed: __http_do_map and
__http_do_map_to_file (ElMap-accepting variants to avoid needing map
iteration in El).
Will Anderson