Move the inline ADD_SCRIPT string into add.lua beside its module in both
languages, matching cas.lua and append.lua: python reads it through
importlib.resources and registers it (EVALSHA), typescript reads it
relative to import.meta.url and tsup copies it beside the bundle.
Registering the script drops the cast around the raw eval call.
The two inline copies had already drifted on indentation, so add a
tests/test_lua_parity.py guard over every lua pair in the repo: same
basename set, unique basenames (dist copies land flat), byte-identical
contents. cas.lua had no drift guard before; append.lua's now-redundant
one is removed.
Also fold the repeated data/meta key joins into helpers on both stores.
Zecheng Zhang
0d5c6650a3