[WAF] Add changelog entry (#22292)

Author: pedrosousa

src/assets/images/changelog/waf/2025-05-payload-logging-update.png

@@ -0,0 +1,19 @@
+---
+title: Improved Payload Logging for WAF Managed Rules
+description: We have upgraded WAF Payload Logging to enhance rule diagnostics and usability.
+products:
+  - waf
+date: 2025-05-08T11:00:00Z
+---
+
+We have upgraded WAF Payload Logging to enhance rule diagnostics and usability:
+
+- **Targeted logging**: Logs now capture only the specific portions of requests that triggered WAF rules, rather than entire request segments.
+- **Visual highlighting**: Matched content is visually highlighted in the UI for faster identification.
+- **Enhanced context**: Logs now include surrounding context to make diagnostics more effective.
+
+![Log entry showing payload logging details](~/assets/images/changelog/waf/2025-05-payload-logging-update.png)
+
+Payload Logging is available to all Enterprise customers. If you have not used Payload Logging before, check how you can [get started](/waf/managed-rules/payload-logging/).
+
+**Note:** The structure of the `encrypted_matched_data` field in Logpush has changed from `Map<Field, Value>` to `Map<Field, {Before: bytes, Content: Value, After: bytes}>`. If you rely on this field in your Logpush jobs, you should review and update your processing logic accordingly.