honcho_conclude's delete action was unreachable in practice: no tool ever
surfaced a real conclusion id for the model to pass as delete_id.
honcho_search only searches the separate Message resource space, and the
SDK's ConclusionScope.list()/.query() (which do return real Conclusion.id
values) were never wired into any tool.
Adds an optional list mode to honcho_conclude (query to search, omit to
browse recent conclusions), backed by a new
HonchoSessionManager.list_conclusions(). No new tool, no changes to the
create/delete signatures or their conclusions_of() routing.
f4669f34cf