Read an intermediate delivery notification as a report, and keep it out of the merge

todo.md

@@ -64,6 +64,7 @@ Rules the API follows:
 | The hold released exactly when the peer was answered: a refused `sendResp()` keeps it, a listener that rejected drops it | `test/session-extras.test.ts` |
 | Every runnable README example | `test/readme.test.ts` |
 | Receipt-versus-message classification by `esm_class` | `test/dlr.test.ts`, `test/session.test.ts` |
+| An intermediate delivery notification read as a report marked `intermediate`, and never counted into a merge | `test/dlr.test.ts`, `test/session.test.ts`, `test/session-extras.test.ts` |
 | A listener that throws, or rejects, reaching `sessionError`/`serverError` rather than the process | `test/session.test.ts`, `test/error-from.test.ts` |
 | Cross-checked against node-smpp both ways and over a live session | `test/interop.test.ts` |
 | CI on Node 18/20/22/24, Renovate, tag-triggered publish | `.github/workflows/` |
@@ -131,13 +132,6 @@ session message is a change to every call site.
       and applies it to the other is wrong. A budget type both take would close it. Raised by review,
       2026-09-01.
 
-- [ ] **Does an intermediate delivery notification deserve to be a `dlr`?** `esm_class` message type
-      `INTERMEDIATE_DELIVERY` (0x20) is classified as a message today, so a peer that reports
-      non-final states with it hands the application a raw `id:… stat:ENROUTE` text as an inbound
-      SMS. Kannel treats 0x04, 0x08 and 0x20 alike as report-bearing. Against it: a non-final report
-      would take a segment's slot in `DlrMerger` and complete the group early. Raised by review,
-      2026-08-27; needs a decision.
-
 - [ ] **`once()` is copied into four test files, and two copies never give up.**
       `session-extras.test.ts` and `readme.test.ts` reject after 5000 ms; `session.test.ts` and
       `tls.test.ts` wait forever, so an event that never fires still hangs the run the way an