fix(whatsapp): remove exposeErrorText config (#74642)

* fix(whatsapp): remove exposeErrorText config

* fix(whatsapp): mark internal system events trusted

docs/.generated/config-baseline.sha256

@@ -1,4 +1,4 @@
-bfd8b3ddcac047e486e9c43fdedc002cb9bf87b659f6563f9f11c850c5b2aaef  config-baseline.json
+2af6bef21f530dc64e0379f7631bed410aee1d5c86604ef9fb149f546cfcb0e8  config-baseline.json
 8d75df355b7f6e44b9c2f195d9df86130beb697e26061469df7d60b7e8a2f204  config-baseline.core.json
-9f5fad66a49fa618d64a963470aa69fed9fe4b4639cc4321f9ec04bfb2f8aa50  config-baseline.channel.json
+fab66aa304db5697e87259165ad261006719eb6e6cdbd25f957fcba2b7b324e9  config-baseline.channel.json
 c4231c2194206547af8ad94342dc00aadb734f43cb49cc79d4c46bdbb80c3f95  config-baseline.plugin.json

docs/channels/whatsapp.md

@@ -398,22 +398,6 @@ When the linked self number is also present in `allowFrom`, WhatsApp self-chat s
   </Accordion>
 </AccordionGroup>
 
-## Error visibility
-
-`channels.whatsapp.exposeErrorText` controls whether agent/provider error text is delivered back into WhatsApp. The default is `true`. Set it to `false` to keep failures quiet on WhatsApp while preserving other channel behavior.
-
-```json5
-{
-  channels: {
-    whatsapp: {
-      exposeErrorText: false,
-    },
-  },
-}
-```
-
-Per-account overrides use `channels.whatsapp.accounts.<id>.exposeErrorText`.
-
 ## Reply quoting
 
 WhatsApp supports native reply quoting, where outbound replies visibly quote the inbound message. Control it with `channels.whatsapp.replyToMode`.
@@ -681,7 +665,7 @@ Primary reference:
 High-signal WhatsApp fields:
 
 - access: `dmPolicy`, `allowFrom`, `groupPolicy`, `groupAllowFrom`, `groups`
-- delivery: `textChunkLimit`, `chunkMode`, `mediaMaxMb`, `sendReadReceipts`, `ackReaction`, `reactionLevel`, `exposeErrorText`
+- delivery: `textChunkLimit`, `chunkMode`, `mediaMaxMb`, `sendReadReceipts`, `ackReaction`, `reactionLevel`
 - multi-account: `accounts.<id>.enabled`, `accounts.<id>.authDir`, account-level overrides
 - operations: `configWrites`, `debounceMs`, `web.enabled`, `web.heartbeatSeconds`, `web.reconnect.*`, `web.whatsapp.*`
 - session behavior: `session.dmScope`, `historyLimit`, `dmHistoryLimit`, `dms.<id>.historyLimit`