Update README.md

Author: malczuuu

problem4j-spring-web/README.md

@@ -10,6 +10,7 @@
 6. [General HTTP Stuff](#general-http-stuff)
 
 ## Overview
+
 This module overrides Spring Web's default (often minimal or plain-text) responses for many framework exceptions and
 produces structured RFC 7807 `Problem` objects. [`ExceptionMappingConfiguration`][ExceptionMappingConfiguration]
 registers these mappings.
@@ -77,7 +78,7 @@ To extract values from target exception, it's possible to use placeholders for i
 
 ```java
 /**
-  * <pre>{@code
+ * <pre>{@code
  * {
  *   "type": "https://example.com/errors/invalid-request",
  *   "title": "Invalid Request",
@@ -137,7 +138,9 @@ property `spring.validation.method.adapt-constraint-violations` to `true`. Enabl
 not rely on raw `ConstraintViolationException`, but rather on `MethodValidationException`, which contains more details
 about validated element.
 
-Let's say we have following `@RestController`, where `idx` query param has different Java parameter name.
+Let's say we have following `@RestController`, where `customerId` query param has different Java parameter name (its
+`String customerIdParam`). We would like to have `customerId` in our response body as potential API clients do not have
+knowledge about internal technologies used by backend.
 
 ```java
 @Validated
@@ -250,7 +253,7 @@ Example:
    }
    ```
 5. If passing request that's too large by configuration, service will write following response. Note that reason phrase
-   for `413` was changed into `Content Too Large` in [RFC 9110 §15.5.14][rfc9110-15.5.4]. 
+   for `413` was changed into `Content Too Large` in [RFC 9110 §15.5.14][rfc9110-15.5.4].
    ```json
    {
      "status": 413,