When a script/txt/csv child is renamed by name_for_inst (e.g. "Init" →
"_Init.luau"), the adjacent meta file must follow the same name. All
three callers were using the Roblox instance name to construct the meta
path, producing "Init.meta.json" instead of "_Init.meta.json" — which
collides with the parent directory's "init.meta.json" on
case-insensitive file systems.
Fix by deriving the meta stem from the first dot-segment of the
snapshot path file name, which already holds the resolved name.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>