Add missing time-series aggs to documentation

docs/reference/query-languages/esql/_snippets/lists/time-series-aggregation-functions.md

@@ -2,7 +2,11 @@
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`AVG_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-avg_over_time)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`COUNT_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-count_over_time)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`COUNT_DISTINCT_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-count_distinct_over_time)
+* {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`DELTA`](../../functions-operators/time-series-aggregation-functions.md#esql-rate)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`FIRST_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-first_over_time)
+* {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`INCREASE`](../../functions-operators/time-series-aggregation-functions.md#esql-rate)
+* {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`IDELTA`](../../functions-operators/time-series-aggregation-functions.md#esql-rate)
+* {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`IRATE`](../../functions-operators/time-series-aggregation-functions.md#esql-rate)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`LAST_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-last_over_time)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`MAX_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-max_over_time)
 * {applies_to}`stack: preview 9.2` {applies_to}`serverless: preview` [`MIN_OVER_TIME`](../../functions-operators/time-series-aggregation-functions.md#esql-min_over_time)

docs/reference/query-languages/esql/functions-operators/time-series-aggregation-functions.md

@@ -25,9 +25,21 @@ supports the following time series aggregation functions:
 :::{include} ../_snippets/functions/layout/count_distinct_over_time.md
 :::
 
+:::{include} ../_snippets/functions/layout/delta.md
+:::
+
 :::{include} ../_snippets/functions/layout/first_over_time.md
 :::
 
+:::{include} ../_snippets/functions/layout/increase.md
+:::
+
+:::{include} ../_snippets/functions/layout/idelta.md
+:::
+
+:::{include} ../_snippets/functions/layout/irate.md
+:::
+
 :::{include} ../_snippets/functions/layout/last_over_time.md
 :::
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Delta.java

@@ -48,8 +48,7 @@ public class Delta extends TimeSeriesAggregateFunction implements OptionalArgume
         description = "Calculates the absolute change of a gauge field in a time window.",
         appliesTo = { @FunctionAppliesTo(lifeCycle = FunctionAppliesToLifecycle.PREVIEW, version = "9.2.0") },
         preview = true,
-        examples = { @Example(file = "k8s-timeseries-delta", tag = "delta") },
-        note = "Available with the [TS](/reference/query-languages/esql/commands/source-commands.md#esql-ts) command"
+        examples = { @Example(file = "k8s-timeseries-delta", tag = "delta") }
     )
     public Delta(Source source, @Param(name = "field", type = { "long", "integer", "double" }) Expression field) {
         this(source, field, new UnresolvedAttribute(source, "@timestamp"));