fix: Share the portable event contract

A parity audit found portable events with different names and fields in
Ruby and JavaScript. Only the timeout event had a shared fixture, so no
test found the difference.

compatibility/telemetry-events.json now holds the attribute allowlist
and the exact keys of each core SQL event. Both test suites read the
same file.

- Rename payload_broadcast_failed to payload_broadcast.failed, the
  dotted form that all other events use.
- Send operation, deliveryMode, retryable, outcome, commitAction, and
  the outbox identity, as JavaScript already does.
- Log exporter and observer failures. Ruby discarded them before.
- Require an observer block and accept at most 1,000 observers.
- Pin reserved JSON keys through actor arguments, state, and results.

Author: cardmagic

CHANGELOG.md

@@ -2,6 +2,22 @@
 
 ## Unreleased
 
+- Rename `solid_objects.payload_broadcast_failed` to
+  `solid_objects.payload_broadcast.failed`, the dotted form that every other
+  event uses. Update Active Support subscribers to the new name. The portable
+  event names the payload `payload`.
+- Match portable event attributes to JavaScript through the shared
+  `compatibility/telemetry-events.json` contract. Message events carry
+  `operation` and `deliveryMode`, `message.failed` carries `retryable` and
+  `outcome`, commit action events carry the message fields and `commitAction`,
+  and `reminder.enqueued` carries `operation`. `outbox.age` carries the effect or
+  broadcast identity, `sync.enqueue_timeout` carries `timeoutMilliseconds`, and
+  polling intervals are integers. `realtime.connected` carries only actor fields.
+- Log `solid_objects.instrumentation.failed` when an exporter or observer raises.
+  Observers require a block, a process accepts at most 1,000 observers, and
+  `SolidObjects.reset!` removes them. Pin reserved JSON keys through actor
+  arguments, state, and retained results.
+
 - Guard personalized payload projections against state changes, staged work,
   and application database writes. Each payload gets an isolated actor from
   the committed snapshot and honors `max_payload_bytes`, matching JavaScript.