BREAKING CHANGE!:
1. remove sql_prepare from the export list;
2. introduce sql_prepare_ext.

The sql_prepare symbol previously included the tarantool port as
an output parameter. However, this structure was inconvenient for
libraries using the C API, as they primarily required just the
statement ID. To address this issue, the sql_prepare symbol was
replaced with the sql_prepare_ext symbol.

NO_DOC=picodata internal patch
NO_CHANGELOG=picodata internal patch