Add doc for min/max_over_time (#130269)

Add the initial docs structure for the TS command and time-series aggregation.
More content will be added later.

Author: dnhatn

docs/reference/query-languages/esql/_snippets/commands/layout/ts.md

@@ -0,0 +1,28 @@
+## `TS` [esql-ts]
+
+The `TS` command is similar to the `FROM` source command,
+but with two key differences: it targets only [time-series indices](docs-content://manage-data/data-store/data-streams/time-series-data-stream-tsds.md)
+and enables the use of time-series aggregation functions
+with the [STATS](/reference/query-languages/esql/commands/processing-commands.md#esql-stats-by) command.
+
+**Syntax**
+
+```esql
+TS index_pattern [METADATA fields]
+```
+
+**Parameters**
+
+`index_pattern`
+:   A list of indices, data streams or aliases. Supports wildcards and date math.
+
+`fields`
+:   A comma-separated list of [metadata fields](/reference/query-languages/esql/esql-metadata-fields.md) to retrieve.
+
+**Examples**
+
+```esql
+TS metrics
+| STATS sum(last_over_time(memory_usage))
+```
+

docs/reference/query-languages/esql/_snippets/functions/description/avg_over_time.md

@@ -1,10 +1,13 @@
 * [`AVG`](../../functions-operators/aggregation-functions.md#esql-avg)
+* [unavailable] [`AVG_OVER_TIME`](../../functions-operators/aggregation-functions.md#esql-avg_over_time)
 * [`COUNT`](../../functions-operators/aggregation-functions.md#esql-count)
 * [`COUNT_DISTINCT`](../../functions-operators/aggregation-functions.md#esql-count_distinct)
 * [`MAX`](../../functions-operators/aggregation-functions.md#esql-max)
+* [unavailable] [`MAX_OVER_TIME`](../../functions-operators/aggregation-functions.md#esql-max_over_time)
 * [`MEDIAN`](../../functions-operators/aggregation-functions.md#esql-median)
 * [`MEDIAN_ABSOLUTE_DEVIATION`](../../functions-operators/aggregation-functions.md#esql-median_absolute_deviation)
 * [`MIN`](../../functions-operators/aggregation-functions.md#esql-min)
+* [unavailable] [`MIN_OVER_TIME`](../../functions-operators/aggregation-functions.md#esql-min_over_time)
 * [`PERCENTILE`](../../functions-operators/aggregation-functions.md#esql-percentile)
 * [preview] [`ST_CENTROID_AGG`](../../functions-operators/aggregation-functions.md#esql-st_centroid_agg)
 * [preview] [`ST_EXTENT_AGG`](../../functions-operators/aggregation-functions.md#esql-st_extent_agg)

docs/reference/query-languages/esql/_snippets/functions/description/max_over_time.md

@@ -1,3 +1,4 @@
 * [`FROM`](../../commands/source-commands.md#esql-from)
+* [`TS`](../../commands/source-commands.md#esql-ts)
 * [`ROW`](../../commands/source-commands.md#esql-row)
 * [`SHOW`](../../commands/source-commands.md#esql-show)

docs/reference/query-languages/esql/_snippets/functions/description/min_over_time.md

@@ -20,6 +20,9 @@ An {{esql}} source command produces a table, typically with data from {{es}}. An
 :::{include} ../_snippets/commands/layout/from.md
 :::
 
+:::{include} ../_snippets/commands/layout/ts.md
+:::
+
 :::{include} ../_snippets/commands/layout/row.md
 :::
 

docs/reference/query-languages/esql/_snippets/functions/examples/avg_over_time.md

@@ -15,6 +15,9 @@ The [`STATS`](/reference/query-languages/esql/commands/processing-commands.md#es
 :::{include} ../_snippets/functions/layout/avg.md
 :::
 
+:::{include} ../_snippets/functions/layout/avg_over_time.md
+:::
+
 :::{include} ../_snippets/functions/layout/count.md
 :::
 
@@ -24,6 +27,9 @@ The [`STATS`](/reference/query-languages/esql/commands/processing-commands.md#es
 :::{include} ../_snippets/functions/layout/max.md
 :::
 
+:::{include} ../_snippets/functions/layout/max_over_time.md
+:::
+
 :::{include} ../_snippets/functions/layout/median.md
 :::
 
@@ -33,6 +39,9 @@ The [`STATS`](/reference/query-languages/esql/commands/processing-commands.md#es
 :::{include} ../_snippets/functions/layout/min.md
 :::
 
+:::{include} ../_snippets/functions/layout/min_over_time.md
+:::
+
 :::{include} ../_snippets/functions/layout/percentile.md
 :::