T-315 (task): add a client-side stdin path to the clide CLI so
commands can take a piped JSON payload (`… | clide icon show
--stdin`), the ergonomic peer of --file. Generic infra slurped in
lib/src/cli/ before the IpcRequest is sent; commands opt in via
CommandSchema. Unblocks the piped variants of T-313/T-316.
T-316 (task): give `clide image show` the same metadata plumbing
as the icon card — a JSON payload (--file, or --stdin once T-315
lands) carrying label/description/captions so images can be
annotated, extending ImageMessage + the image card. Starts with
text metadata; visual marker overlays flagged as a follow-up.
Existing `image show <path> --caption` form stays unchanged.
Both under UI epic T-276; cross-linked from T-313.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
jpmschweitzerandClaude Opus 4.8
db66039769