primaryModel was being set to the model that performed the merge (or,
in AI mode, stamped onto every synthesized message). It should instead
be the most recently used model among the source conversations being
combined.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Lets users multi-select 2+ saved conversations and merge them into one,
either by chronological concatenation or by having the default model
synthesize a single coherent conversation from the source transcripts.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>