Update README Spring Boot compatibility to 4.1.x

Update the README table to extend the Spring Boot compatibility range for the `main` branch from 4.0.x to 4.1.x. The listed latest version (`0.2.21`) remains unchanged; this is a documentation-only change.

Author: mercyblitz

README.md

@@ -110,7 +110,7 @@ Choose the version that matches your Spring Boot generation:
 
 | Branch | Spring Boot Compatibility | Latest Version |
 |--------|---------------------------|----------------|
-| `main` | 3.0.x – 3.5.x, 4.0.x      | `0.2.21`       |
+| `main` | 3.0.x – 3.5.x, 4.1.x      | `0.2.21`       |
 | `1.x`  | 2.0.x – 2.7.x             | `0.1.21`       |
 
 ### Add Module Dependencies