Allow ExchangeStrategies customizations in WebClient

Backport of d4209392 and acfeb77d

Closes gh-23961

src/docs/asciidoc/web/webflux-webclient.adoc

@@ -42,17 +42,14 @@ The following example configures <<web-reactive.adoc#webflux-codecs, HTTP codecs
 [source,java,intent=0]
 [subs="verbatim,quotes"]
 ----
-	ExchangeStrategies strategies = ExchangeStrategies.builder()
-			.codecs(configurer -> {
-				// ...
+	WebClient client = WebClient.builder()
+			.exchangeStrategies(builder -> {
+					return builder.codecs(codecConfigurer -> {
+						//...
+					});
 			})
 			.build();
-
-	WebClient client = WebClient.builder()
-			.exchangeStrategies(strategies)
-			.build();
 ----
-====
 
 Once built, a `WebClient` instance is immutable. However, you can clone it and build a
 modified copy without affecting the original instance, as the following example shows:
@@ -73,6 +70,31 @@ modified copy without affecting the original instance, as the following example
 ----
 ====
 
+[[webflux-client-builder-maxinmemorysize]]
+=== MaxInMemorySize
+
+Spring WebFlux configures <<web-reactive.adoc#webflux-codecs-limits,limits>> for buffering
+data in-memory in codec to avoid application memory issues. By the default this is
+configured to 256KB and if that's not enough for your use case, you'll see the following:
+
+----
+org.springframework.core.io.buffer.DataBufferLimitException: Exceeded limit on max bytes to buffer
+----
+
+You can configure this limit on all default codecs with the following code sample:
+
+[source,java,indent=0,subs="verbatim,quotes",role="primary"]
+.Java
+----
+	WebClient webClient = WebClient.builder()
+			.exchangeStrategies(builder ->
+				builder.codecs(codecs ->
+					codecs.defaultCodecs().maxInMemorySize(2 * 1024 * 1024)
+				)
+			)
+			.build();
+----
+
 
 
 [[webflux-client-builder-reactor]]

src/docs/asciidoc/web/webflux.adoc

@@ -776,7 +776,8 @@ To configure buffer sizes, you can check if a given `Decoder` or `HttpMessageRea
 exposes a `maxInMemorySize` property and if so the Javadoc will have details about default
 values. In WebFlux, the `ServerCodecConfigurer` provides a
 <<webflux-config-message-codecs,single place>> from where to set all codecs, through the
-`maxInMemorySize` property for default codecs.
+`maxInMemorySize` property for default codecs. On the client side, the limit can be changed
+in <<web-reactive.adoc#webflux-client-builder-maxinmemorysize, WebClient.Builder>>.
 
 For <<webflux-codecs-multipart,Multipart parsing>> the `maxInMemorySize` property limits
 the size of non-file parts. For file parts it determines the threshold at which the part