Seeding additionalDirectories at launch (via --add-dir or the
workspace.additionalDirectories setting) called #rewriteAtomically on a
brand-new session manager, which materialized a header-only JSONL and a
fresh breadcrumb before any assistant output. Launching and exiting with
configured roots therefore created an empty resumable session that
--continue picked over the previous conversation.
Gated all three workspace-directory mutators behind the existing
#shouldHaveSessionFile() lazy-persistence gate (one shared helper), and
made setAdditionalDirectories a no-op when the normalized list is
unchanged so resuming large sessions no longer rewrites the whole JSONL
on every startup. Roots set before the gate is crossed land in the
header with the first durable write; added a regression test.
can1357
bcd23ee7c1