select.lua: add this script

This adds script messages to select playlist entries, tracks, chapters,
subtitle lines, bindings and properties using the newly introduced
mp.input.select().

This fully closes #13964.

DOCS/man/mpv.rst

@@ -270,6 +270,46 @@ Alt+2 (and Command+2 on macOS)
 Command + f (macOS only)
     Toggle fullscreen (see also ``--fs``).
 
+(The following keybindings open a selector in the console that lets you choose
+from a list of items by typing part of the desired item and/or by navigating
+them with keybindings: ``Down`` and ``Ctrl+n`` go down, ``Up`` and ``Ctrl+p`` go
+up, ``Page down`` and ``Ctrl+f`` scroll down one page, and ``Page up`` and
+``Ctrl+b`` scroll up one page.)
+
+g-p
+    Select a playlist entry.
+
+g-s
+    Select a subtitle track.
+
+g-S
+    Select a secondary subtitle track.
+
+g-a
+    Select an audio track.
+
+g-v
+    Select a video track.
+
+g-t
+    Select a track of any type.
+
+g-c
+    Select a chapter.
+
+g-l
+    Select a subtitle line to seek to. This currently requires ``ffmpeg`` in
+    ``PATH``, or in the same folder as mpv on Windows.
+
+g-d
+    Select an audio device.
+
+g-b
+    Select a defined input binding.
+
+g-r
+    Show the values of all properties.
+
 (The following keys are valid if you have a keyboard with multimedia keys.)
 
 PAUSE

DOCS/man/options.rst

@@ -1023,6 +1023,10 @@ Program Behavior
     `Conditional auto profiles`_ for details. ``auto`` will load the script,
     but immediately unload it if there are no conditional profiles.
 
+``--load-select=<yes|no>``
+    Enable the builtin script that lets you select from lists of items (default:
+    yes). By default, its keybindings start with the ``g`` key.
+
 ``--player-operation-mode=<cplayer|pseudo-gui>``
     For enabling "pseudo GUI mode", which means that the defaults for some
     options are changed. This option should not normally be used directly, but