revert: restore dafit's Publish-Subscribe.md to his own content; my additions overstepped

learning/Publish-Subscribe.md

@@ -80,42 +80,4 @@ Multiple services subscribe and each reacts differently:
     3.Analytics Service records metrics
     4.Shipping Service prepares the shipment
 
-One publish, four independent reactions — no coordination needed.
-
----
-
-## The goldfish boundary (what this paper describes, precisely)
-
-Everything above is *core NATS*: fire-and-forget, delivered to active
-subscribers only, discarded if no one listens. No memory. We found this
-the live way on 2026-11-06: `nats sub "dev.>"` caught `dev.test.hello`
-while the terminal sat open, and the bus has no record of it since.
-
-JetStream adds the memory: streams claim subjects, messages are stored,
-durable consumers replay and each tracks its own position.
-
-## Estate mapping (our reality, host-verified)
-
-| Item | Value | Truth of record |
-|------|-------|-----------------|
-| Bus | `nats-dev.eachpath.local:30000` (VM 122) | [host record](../../eachpath.local/saturn.eachpath.local/vms/nats-dev.eachpath.local/nats-dev.eachpath.local.md) |
-| Streams | `REGISTER` -> `nimmerverse.register.>` (durable), `CYCLE` -> `nimmerverse.cycle.>` (100k msgs) | host record, 2026-11-06 |
-| Publisher hosts | aynee (nats-cli + nats-py 2.16.0 in nimmer-lib venv), nimmerworld-dev | both, 2026-11-06 |
-| Core-mode example | `dev.test.hello` = "Hello Nimmerverse!": live delivery only, in NO stream | verified 2026-11-06 |
-
-Note: the generic example `orders.created` has no stream here; on OUR
-estate, subjects without a stream are transient by design. Our persistent
-naming is `nimmerverse.*` under the two streams above.
-
-## Drills (run on our estate, record answers in section 5 of the 101 paper)
-
-1. Terminal A (nimmerworld-dev): `nats pub nimmerverse.cycle.hello "dafit was here"`
-   Terminal B (aynee): `nats sub "nimmerverse.cycle.*"` - watch the `*`
-   match exactly one token.
-2. `nats stream info CYCLE` - the bus has now *counted* the message.
-3. Kill both terminals, start a subscriber again: core-mode subject is
-   empty, stream subject replays its history. That contrast IS the lesson.
-
-## Understand-check (ten words, said back before any primitive builds on this)
-
-> dafit's version: (to be said back)
+One publish, four independent reactions — no coordination needed.