Add examples and docs for function named parameters

Author: carlosdelest

docs/reference/esql/esql-syntax.asciidoc

@@ -169,3 +169,48 @@ Timespan literals are not whitespace sensitive. These expressions are all valid:
 * `1 day`
 * `1       day`
 
+[discrete]
+[[esql-function-named-params]]
+==== Function named parameters
+
+Some functions like <<esql-match,match>> use named parameters to provide additional options.
+
+Named parameters allow specifying name value pairs, using the following syntax:
+
+`{"option_name": option_value, "another_option_name": another_value}`
+
+Valid value types are strings, numbers and booleans.
+
+An example using <<esql-match,match>>:
+
+[source,console]
+----
+POST /_query
+{
+"query": """
+FROM library
+| WHERE match(author, "Frank Herbert", {"minimum_should_match": 2, "operator": "AND"})
+"""
+}
+----
+// TEST[setup:library]
+
+You can also use <<esql-rest-params,query parameters>> in function named parameters:
+
+[source,console]
+----
+POST /_query
+{
+"query": """
+FROM library
+| EVAL year = DATE_EXTRACT("year", release_date)
+| WHERE page_count > ? AND match(author, ?, {"minimum_should_match": ?})
+| STATS count = COUNT(*) by year
+| WHERE count > ?
+| LIMIT 5
+""",
+"params": [300, "Frank Herbert", 2]
+}
+----
+// TEST[setup:library]
+

docs/reference/esql/functions/description/match.asciidoc

@@ -694,13 +694,17 @@ testMatchWithOptionsOperator
 required_capability: match_function
 required_capability: match_function_options
 
-from books 
-| where match(title, "Hobbit Back Again", {"operator": "AND"})
-| keep title;
+// tag::match-with-named-function-params[]
+FROM books 
+| WHERE MATCH(title, "Hobbit Back Again", {"operator": "AND"})
+| KEEP title;
+// end::match-with-named-function-params[]
 
+// tag::match-with-named-function-params-result[]
 title:text
 The Hobbit or There and Back Again
 ;
+// end::match-with-named-function-params-result[]
 
 testMatchWithOptionsMinimumShouldMatch
 required_capability: match_function

docs/reference/esql/functions/examples/match.asciidoc

@@ -156,10 +156,15 @@ public class Match extends FullTextFunction implements PostOptimizationVerificat
             Match can be used on fields from the text family like <<text, text>> and <<semantic-text, semantic_text>>,
             as well as other field types like keyword, boolean, dates, and numeric types.
 
+            Match can use <<esql-function-named-params,function named parameters>> to specify additional options for the match query.
+            All <<match-field-params,match query parameters>> are supported.
+
             For a simplified syntax, you can use the <<esql-search-operators,match operator>> `:` operator instead of `MATCH`.
 
             `MATCH` returns true if the provided query matches the row.""",
-        examples = { @Example(file = "match-function", tag = "match-with-field") }
+        examples = {
+            @Example(file = "match-function", tag = "match-with-field"),
+            @Example(file = "match-function", tag = "match-with-named-function-params") }
     )
     public Match(
         Source source,