0672 — Client results remain unnamed

Context

The named-return-params roadmap task considered naming every result as signature documentation. A trial covered nine client, topic-handle, and producer functions, with explicit return expressions retained. Review through the playground call sites showed that the client design already makes the results clear: the verb and concrete return type identify what comes back.

Decision

• Revert the nine trial signatures and retain unnamed results by default on the client, handles, and instances, including constructors.
• Do not standardize named results as an additional documentation layer; in this API they repeat information without resolving ambiguity.
• Keep return expressions explicit. This decision does not ban named results needed by an implementation, such as deferred result handling.
• Close the roadmap task without a repository-wide signature sweep.

Consequences

The playgrounds and runtime behavior are unchanged. Existing named results elsewhere are untouched. CONVENTIONS.md records the client-surface default; mandatory named results should not be proposed again without new evidence of ambiguity in that surface.