ESQL: Rename AUTO_BUCKET to just BUCKET (#107197)

This renames the function AUTO_BUCKET to just BUCKET.
It also removes the experimental tagging of the function in the docs, making it generally available.

docs/reference/esql/esql-get-started.asciidoc

@@ -240,30 +240,30 @@ include::{esql-specs}/eval.csv-spec[tag=gs-eval-stats-backticks]
 === Create a histogram
 
 To track statistics over time, {esql} enables you to create histograms using the
-<<esql-auto_bucket>> function. `AUTO_BUCKET` creates human-friendly bucket sizes
+<<esql-bucket>> function. `BUCKET` creates human-friendly bucket sizes
 and returns a value for each row that corresponds to the resulting bucket the
 row falls into.
 
 For example, to create hourly buckets for the data on October 23rd:
 
 [source,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=gs-auto_bucket]
+include::{esql-specs}/date.csv-spec[tag=gs-bucket]
 ----
 
-Combine `AUTO_BUCKET` with <<esql-stats-by>> to create a histogram. For example,
+Combine `BUCKET` with <<esql-stats-by>> to create a histogram. For example,
 to count the number of events per hour:
 
 [source,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=gs-auto_bucket-stats-by]
+include::{esql-specs}/date.csv-spec[tag=gs-bucket-stats-by]
 ----
 
 Or the median duration per hour:
 
 [source,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=gs-auto_bucket-stats-by-median]
+include::{esql-specs}/date.csv-spec[tag=gs-bucket-stats-by-median]
 ----
 
 [discrete]

docs/reference/esql/functions/auto_bucket.asciidoc → docs/reference/esql/functions/bucket.asciidoc

@@ -1,14 +1,12 @@
 [discrete]
-[[esql-auto_bucket]]
-=== `AUTO_BUCKET`
-
-experimental::[]
+[[esql-bucket]]
+=== `BUCKET`
 
 *Syntax*
 
 [source,esql]
 ----
-AUTO_BUCKET(expression, buckets, from, to)
+BUCKET(expression, buckets, from, to)
 ----
 
 *Parameters*
@@ -28,68 +26,68 @@ End of the range. Can be a number or a date expressed as a string.
 *Description*
 
 Creates human-friendly buckets and returns a value for each row that corresponds
-to the resulting bucket the row falls into. 
+to the resulting bucket the row falls into.
 
 Using a target number of buckets, a start of a range, and an end of a range,
-`AUTO_BUCKET` picks an appropriate bucket size to generate the target number of
+`BUCKET` picks an appropriate bucket size to generate the target number of
 buckets or fewer. For example, asking for at most 20 buckets over a year results
 in monthly buckets:
 
 [source.merge.styled,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketMonth]
+include::{esql-specs}/date.csv-spec[tag=docsBucketMonth]
 ----
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketMonth-result]
+include::{esql-specs}/date.csv-spec[tag=docsBucketMonth-result]
 |===
 
 The goal isn't to provide *exactly* the target number of buckets, it's to pick a
 range that people are comfortable with that provides at most the target number
 of buckets.
 
-Combine `AUTO_BUCKET` with
+Combine `BUCKET` with
 <<esql-stats-by>> to create a histogram:
 
 [source.merge.styled,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketMonthlyHistogram]
+include::{esql-specs}/date.csv-spec[tag=docsBucketMonthlyHistogram]
 ----
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketMonthlyHistogram-result]
+include::{esql-specs}/date.csv-spec[tag=docsBucketMonthlyHistogram-result]
 |===
 
-NOTE: `AUTO_BUCKET` does not create buckets that don't match any documents.
+NOTE: `BUCKET` does not create buckets that don't match any documents.
 That's why this example is missing `1985-03-01` and other dates.
 
 Asking for more buckets can result in a smaller range. For example, asking for
 at most 100 buckets in a year results in weekly buckets:
 
 [source.merge.styled,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketWeeklyHistogram]
+include::{esql-specs}/date.csv-spec[tag=docsBucketWeeklyHistogram]
 ----
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketWeeklyHistogram-result]
+include::{esql-specs}/date.csv-spec[tag=docsBucketWeeklyHistogram-result]
 |===
 
-NOTE: `AUTO_BUCKET` does not filter any rows. It only uses the provided range to
+NOTE: `BUCKET` does not filter any rows. It only uses the provided range to
 pick a good bucket size. For rows with a value outside of the range, it returns
 a bucket value that corresponds to a bucket outside the range. Combine
-`AUTO_BUCKET` with <<esql-where>> to filter rows.
+`BUCKET` with <<esql-where>> to filter rows.
 
-`AUTO_BUCKET` can also operate on numeric fields. For example, to create a
+`BUCKET` can also operate on numeric fields. For example, to create a
 salary histogram:
 
 [source.merge.styled,esql]
 ----
-include::{esql-specs}/ints.csv-spec[tag=docsAutoBucketNumeric]
+include::{esql-specs}/ints.csv-spec[tag=docsBucketNumeric]
 ----
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-include::{esql-specs}/ints.csv-spec[tag=docsAutoBucketNumeric-result]
+include::{esql-specs}/ints.csv-spec[tag=docsBucketNumeric-result]
 |===
 
 Unlike the earlier example that intentionally filters on a date range, you
@@ -104,17 +102,17 @@ per hour:
 
 [source.styled,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=docsAutoBucketLast24hr]
+include::{esql-specs}/date.csv-spec[tag=docsBucketLast24hr]
 ----
 
 Create monthly buckets for the year 1985, and calculate the average salary by
 hiring month:
 
 [source.merge.styled,esql]
 ----
-include::{esql-specs}/date.csv-spec[tag=auto_bucket_in_agg]
+include::{esql-specs}/date.csv-spec[tag=bucket_in_agg]
 ----
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-include::{esql-specs}/date.csv-spec[tag=auto_bucket_in_agg-result]
+include::{esql-specs}/date.csv-spec[tag=bucket_in_agg-result]
 |===

docs/reference/esql/functions/date-time-functions.asciidoc

@@ -8,7 +8,7 @@
 {esql} supports these date-time functions:
 
 // tag::date_list[]
-* experimental:[] <<esql-auto_bucket>>
+* <<esql-bucket>>
 * <<esql-date_diff>>
 * <<esql-date_extract>>
 * <<esql-date_format>>
@@ -17,7 +17,7 @@
 * <<esql-now>>
 // end::date_list[]
 
-include::auto_bucket.asciidoc[]
+include::bucket.asciidoc[]
 include::date_diff.asciidoc[]
 include::date_extract.asciidoc[]
 include::date_format.asciidoc[]

docs/reference/esql/functions/layout/bucket.asciidoc

@@ -0,0 +1,14 @@
+// This is generated by ESQL's AbstractFunctionTestCase. Do no edit it. See ../README.md for how to regenerate it.
+
+[discrete]
+[[esql-bucket]]
+=== `BUCKET`
+
+*Syntax*
+
+[.text-center]
+image::esql/functions/signature/bucket.svg[Embedded,opts=inline]
+
+include::../parameters/bucket.asciidoc[]
+include::../description/bucket.asciidoc[]
+include::../types/bucket.asciidoc[]