The menu so far only exported the current view (type + search
filter over the page 100-event window). A second action now fetches
the complete event history of the active project scope in one
EventLog call (the RPC has no cursor and no server-side cap) and
writes it as JSONL. Serialisation extracted to a top-level function
with unit tests; a stale comment advertising the never-shipped
"chain audit export" command now names "chain admin events --json".
Studio 0.73.0.
Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>