CAMEL-23264: Address review feedback - remove upgrade guide, add @SInCE tags, regenerate

- Remove Split EIP section from upgrade guide (davsclaus: new features
  don't belong in the upgrade guide, only migration info)
- Add @SInCE 4.21 to SplitResult class and Failure record (oscerd)
- Regenerate all downstream artifacts after rebase onto latest main

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: gnodet

catalog/camel-catalog/src/generated/resources/org/apache/camel/catalog/models/split.json

@@ -13280,7 +13280,12 @@ of one at a time.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting the split operation.
+Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting the split operation. For example, 0.1
+means abort if more than 10% of items fail. When the threshold is exceeded, a org.apache.camel.CamelExchangeException is
+thrown. This option is mutually exclusive with stopOnException . When set, individual item failures are tracked but
+processing continues until the threshold is exceeded. Note: When combined with parallelProcessing , the failure ratio
+may vary between runs because parallel items complete in non-deterministic order. For deterministic abort behavior with
+parallel processing, prefer maxFailedRecords (absolute count) over errorThreshold (ratio).
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -13289,7 +13294,9 @@ Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets the maximum number of failed records before aborting the split operation.
+Sets the maximum number of failed records before aborting the split operation. When the count is exceeded, a
+org.apache.camel.CamelExchangeException is thrown. This option is mutually exclusive with stopOnException . Can be
+combined with errorThreshold processing aborts when either threshold is exceeded.
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -13298,7 +13305,8 @@ Sets the maximum number of failed records before aborting the split operation.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets a reference to a ResumeStrategy in the registry for resume-from-last-position support.
+Sets a ResumeStrategy for resume-from-last-position support. The watermark key must also be configured via
+watermarkKey(String) .
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -13316,7 +13324,8 @@ Sets the key to use in the watermark store.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets a Simple expression to evaluate on the exchange after split completion to determine the new watermark value.
+Sets a Simple expression to evaluate on each completed sub-exchange to determine the new watermark value. When set,
+enables value-based watermarking instead of index-based. The expression is evaluated using the Simple language.
 ]]>
             </xs:documentation>
           </xs:annotation>

catalog/camel-catalog/src/generated/resources/org/apache/camel/catalog/schemas/camel-spring.xsd

@@ -12423,7 +12423,12 @@ of one at a time.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting the split operation.
+Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting the split operation. For example, 0.1
+means abort if more than 10% of items fail. When the threshold is exceeded, a org.apache.camel.CamelExchangeException is
+thrown. This option is mutually exclusive with stopOnException . When set, individual item failures are tracked but
+processing continues until the threshold is exceeded. Note: When combined with parallelProcessing , the failure ratio
+may vary between runs because parallel items complete in non-deterministic order. For deterministic abort behavior with
+parallel processing, prefer maxFailedRecords (absolute count) over errorThreshold (ratio).
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -12432,7 +12437,9 @@ Sets the error threshold as a fraction (0.0-1.0) of failed items before aborting
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets the maximum number of failed records before aborting the split operation.
+Sets the maximum number of failed records before aborting the split operation. When the count is exceeded, a
+org.apache.camel.CamelExchangeException is thrown. This option is mutually exclusive with stopOnException . Can be
+combined with errorThreshold processing aborts when either threshold is exceeded.
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -12441,7 +12448,8 @@ Sets the maximum number of failed records before aborting the split operation.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets a reference to a ResumeStrategy in the registry for resume-from-last-position support.
+Sets a ResumeStrategy for resume-from-last-position support. The watermark key must also be configured via
+watermarkKey(String) .
 ]]>
             </xs:documentation>
           </xs:annotation>
@@ -12459,7 +12467,8 @@ Sets the key to use in the watermark store.
           <xs:annotation>
             <xs:documentation xml:lang="en">
 <![CDATA[
-Sets a Simple expression to evaluate on the exchange after split completion to determine the new watermark value.
+Sets a Simple expression to evaluate on each completed sub-exchange to determine the new watermark value. When set,
+enables value-based watermarking instead of index-based. The expression is evaluated using the Simple language.
 ]]>
             </xs:documentation>
           </xs:annotation>

catalog/camel-catalog/src/generated/resources/org/apache/camel/catalog/schemas/camel-xml-io.xsd

@@ -1,10 +1,14 @@
 /* Generated by camel build tools - do NOT edit this file! */
 package org.apache.camel;
 
-import javax.annotation.processing.Generated;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
+import javax.annotation.processing.Generated;
+
+import org.jspecify.annotations.Nullable;
+
 /**
  * Generated by camel build tools - do NOT edit this file!
  */
@@ -13,7 +17,7 @@ public class ExchangeConstantProvider {
 
     private static final Map<String, String> MAP;
     static {
-        Map<String, String> map = new HashMap<>(151);
+        Map<String, String> map = new HashMap<>(153);
         map.put("AGGREGATED_COLLECTION_GUARD", "CamelAggregatedCollectionGuard");
         map.put("AGGREGATED_COMPLETED_BY", "CamelAggregatedCompletedBy");
         map.put("AGGREGATED_CORRELATION_KEY", "CamelAggregatedCorrelationKey");
@@ -111,6 +115,8 @@ public class ExchangeConstantProvider {
         map.put("MAXIMUM_SIMPLE_CACHE_SIZE", "CamelMaximumSimpleCacheSize");
         map.put("MAXIMUM_TRANSFORMER_CACHE_SIZE", "CamelMaximumTransformerCacheSize");
         map.put("MAXIMUM_VALIDATOR_CACHE_SIZE", "CamelMaximumValidatorCacheSize");
+        map.put("MESSAGE_BODY_SIZE", "CamelMessageBodySize");
+        map.put("MESSAGE_HEADERS_SIZE", "CamelMessageHeadersSize");
         map.put("MESSAGE_HISTORY", "CamelMessageHistory");
         map.put("MESSAGE_HISTORY_HEADER_FORMAT", "CamelMessageHistoryHeaderFormat");
         map.put("MESSAGE_HISTORY_OUTPUT_FORMAT", "CamelMessageHistoryOutputFormat");
@@ -168,8 +174,12 @@ public class ExchangeConstantProvider {
         MAP = map;
     }
 
-    public static String lookup(String key) {
+    public static @Nullable String lookup(String key) {
         return MAP.get(key);
     }
+
+    public static Collection<String> values() {
+        return MAP.values();
+    }
 }
 

core/camel-api/src/generated/java/org/apache/camel/ExchangeConstantProvider.java

@@ -24,6 +24,8 @@
  * when error thresholds ({@code errorThreshold} or {@code maxFailedRecords}) are configured.
  * <p/>
  * This result is available as an exchange property ({@link Exchange#SPLIT_RESULT}) after the split operation completes.
+ *
+ * @since 4.21
  */
 public final class SplitResult {
 
@@ -32,6 +34,7 @@ public final class SplitResult {
      *
      * @param index     the 0-based index of the failed item in the split sequence
      * @param exception the exception that caused the failure
+     * @since           4.21
      */
     public record Failure(int index, Exception exception) {
     }