mod_storage_internal: Lazy-load archive items while iterating

Very large list files previously ran into limits of the Lua parser, or
just caused Prosody to freeze while parsing.

Using the new index we can parse individual items one at a time.  This
probably won't reduce overall CPU usage, probably the opposite, but it
will reduce the number of items in memory at once and allow collection
of items after we iterated past them.

0 files changed, 0 insertions, 0 deletions