Problem

In some channel/public-path conditions, outgoing channel messages can remain in a pending state even after the app receives RESP_CODE_SENT.

Expected Behavior

When RESP_CODE_SENT is received for an outgoing send, the most recent pending outgoing channel message should transition to sent without waiting for a later echo/repeat path event.

Scope

• App-side connector behavior only
• No firmware protocol changes

Acceptance Criteria

• Pending outgoing channel messages are marked sent on first-hop RESP_CODE_SENT
• Existing direct-message behavior is preserved
• No unrelated workspace/tooling changes are included