Move ES|QL sample command from snapshot to tech preview (elastic#129540)

* Move ES|QL sample command from snapshot to tech preview

* dev_sample -> sample

* fix test

* fix grammar

Author: jan-elastic

x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.g4

@@ -70,6 +70,7 @@ LIMIT : 'limit'               -> pushMode(EXPRESSION_MODE);
 MV_EXPAND : 'mv_expand'       -> pushMode(MVEXPAND_MODE);
 RENAME : 'rename'             -> pushMode(RENAME_MODE);
 ROW : 'row'                   -> pushMode(EXPRESSION_MODE);
+SAMPLE : 'sample'             -> pushMode(EXPRESSION_MODE);
 SHOW : 'show'                 -> pushMode(SHOW_MODE);
 SORT : 'sort'                 -> pushMode(EXPRESSION_MODE);
 STATS : 'stats'               -> pushMode(EXPRESSION_MODE);
@@ -91,7 +92,6 @@ DEV_INLINESTATS :  {this.isDevVersion()}? 'inlinestats'   -> pushMode(EXPRESSION
 DEV_LOOKUP :       {this.isDevVersion()}? 'lookup_🐔'     -> pushMode(LOOKUP_MODE);
 DEV_METRICS :      {this.isDevVersion()}? 'metrics'       -> pushMode(METRICS_MODE);
 DEV_RERANK :       {this.isDevVersion()}? 'rerank'        -> pushMode(EXPRESSION_MODE);
-DEV_SAMPLE :       {this.isDevVersion()}? 'sample'        -> pushMode(EXPRESSION_MODE);
 
 // list of all JOIN commands
 DEV_JOIN_FULL :    {this.isDevVersion()}? 'full'          -> pushMode(JOIN_MODE);

x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.tokens

@@ -54,11 +54,11 @@ processingCommand
     | joinCommand
     | changePointCommand
     | completionCommand
+    | sampleCommand
     // in development
     | {this.isDevVersion()}? inlinestatsCommand
     | {this.isDevVersion()}? lookupCommand
     | {this.isDevVersion()}? rerankCommand
-    | {this.isDevVersion()}? sampleCommand
     ;
 
 whereCommand
@@ -356,6 +356,10 @@ changePointCommand
     : CHANGE_POINT value=qualifiedName (ON key=qualifiedName)? (AS targetType=qualifiedName COMMA targetPvalue=qualifiedName)?
     ;
 
+sampleCommand
+    : SAMPLE probability=constant
+    ;
+
 //
 // In development
 //
@@ -390,7 +394,3 @@ rerankCommand
 completionCommand
     : COMPLETION (targetField=qualifiedName ASSIGN)? prompt=primaryExpression WITH inferenceId=identifierOrParameter
     ;
-
-sampleCommand
-    : DEV_SAMPLE probability=constant
-    ;

x-pack/plugin/esql/src/main/antlr/EsqlBaseParser.g4

@@ -961,16 +961,15 @@ public enum Cap {
          * Support for LIKE operator with a list of patterns
          */
         LIKE_WITH_LIST_OF_PATTERNS,
-
         /**
          * Support for the SAMPLE command
          */
-        SAMPLE_V3(Build.current().isSnapshot()),
+        SAMPLE_V3,
 
         /**
          * Support parameters for SAMPLE command.
          */
-        PARAMETER_FOR_SAMPLE(Build.current().isSnapshot());
+        PARAMETER_FOR_SAMPLE;
 
         private final boolean enabled;