Docs: Added v0.25.4 release notes draft. (#14914)

### What problem does this PR solve?

v0.25.4 release notes draft.

### Type of change


- [x] Documentation Update

docs/release_notes.md

@@ -9,6 +9,27 @@ sidebar_custom_props: {
 
 Key features, improvements and bug fixes in the latest releases.
 
+## v0.25.4
+
+Released on May 14, 2026
+
+### New features
+
+- Adds a generic, configuration-driven RESTful API data source connector.
+
+### Improvements
+
+- Agent tag management with filtering and sorting.
+- Widget customization and persistence.
+
+### Model support
+
+- Adds gpt-5.4-mini and gpt-5.4-nano to the OpenAI model list
+
+### Bug fixes
+
+Fixed dataset document download route.
+
 ## v0.25.3
 
 Released on May 13, 2026.
@@ -37,7 +58,6 @@ Released on May 13, 2026.
 - Agent: Template strings in tool-type components like **Email** and **Invoke** failed to interpolate; `{{variable}}` placeholders were passed through as raw text. [#14601](https://github.com/infiniflow/ragflow/pull/14601)
 - Volcengine (Doubao/Ark) endpoints were not visible in the provider list. [#14702](https://github.com/infiniflow/ragflow/pull/14702)
 
-
 ## v0.25.2
 
 Released on May 11, 2026.