Carry the button art in releases and draw the button prompts during the game build.

make_launcher.py and make_kit.py take --prompt-art (folders holding XGamepad, P5Gamepad and Keyboard_Mouse, or those
folders) and copy only the pictures pad_prompts.py reads into the release's prompt-art folder; tools/prompt_art.py
holds the art tables and that list, with no imaging packages. make_game.py's new last step, prompts, runs
pad_prompts.py on that art into the game folder's romfs-patches-* folders. Its key names everything it reads (the
RomFS, the art, the tools, the bind_ lines of nx2navi.ini, the folders being there), so it runs again only when one of
those changed, and it makes no other step run. A kit without art skips it. The launcher's Python gets fonttools and
pillow, and its jobs show a Draw the Button Prompts row when the version has art.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/README-BuildKit.md

@@ -21,11 +21,12 @@ downloads included, and keeps the game up to date. This page is the same build b
    in the installer. Then, in a Command Prompt:
 
    ```bat
-   py -m pip install numpy lz4 zstandard zbic
+   py -m pip install numpy lz4 zstandard zbic fonttools pillow
    ```
 
    `zbic` unpacks the game's compressed program files. It is a separate GPL-2.0 package you install yourself; the kit
-   only calls it.
+   only calls it. `fonttools` and `pillow` draw the Xbox, PlayStation and keyboard and mouse button prompts, when the
+   kit has a `prompt-art` folder.
 
 2. **MSYS2** from [msys2.org](https://www.msys2.org/), installed to the default `C:\msys64`. Open **MSYS2 UCRT64** from
    the Start menu and paste:
@@ -51,9 +52,10 @@ check that your dump is the right version, add `--check` (it builds nothing).
 The build checks the version, unpacks the program files, packs the 26 GB RomFS image (every file is checked against
 the dump's own checksums) while it turns the game's code into C and compiles it (about 6 minutes on a 16-thread
 Ryzen 7; longer on fewer cores), then prepares every one of the game's shaders for your graphics card (about 5 more
-minutes), so the game does not stop to compile shaders while you play. The game it builds is for this PC's processor.
-You can use your PC meanwhile. If it stops,
-run the same command again: finished steps are skipped.
+minutes), so the game does not stop to compile shaders while you play. When the kit has a `prompt-art` folder, it
+last draws the Xbox, PlayStation and keyboard and mouse button prompts from that art (about a minute) into the
+`romfs-patches-*` folders beside the game. The game it builds is for this PC's processor. You can use your PC
+meanwhile. If it stops, run the same command again: finished steps are skipped.
 
 When it says `finished`, start `C:\Games\Ocarina\ocarina.exe`. You can delete `C:\Games\Ocarina\build-cache` (about
 5 GB) afterwards.
@@ -68,6 +70,10 @@ When it says `finished`, start `C:\Games\Ocarina\ocarina.exe`. You can delete `C
 - **Screen** in the menu has Upscaling (DLSS on NVIDIA RTX cards, FSR 3.1 on any card), Frame generation (FSR 3.1; it
   needs DLSS or FSR 3.1 upscaling on), HDR (the game's picture tone mapped to your display, with its own grading rows, or Native, the game's own HDR; turn HDR on in Windows first) and the
   resolution. Those marked "after restart" take effect when the game starts again.
+- **Controls** in the menu has Button prompts: the game's own, or Xbox, PlayStation or keyboard and mouse ones when
+  the build drew them (a kit with `prompt-art`). It takes effect after a restart. The keyboard and mouse prompts show
+  the keys `nx2navi.ini` binds when the build runs: after rebinding keys, run
+  `py -I tools\make_game.py --rebuild --out "C:\Games\Ocarina"` to draw them again (it skips everything else).
 - The build copies NVIDIA's DLSS library `nvngx_dlss.dll` (with `nvngx_dlss-NOTICE.txt`, which names its licence)
   and FSR 3.1's `amd_fidelityfx_vk.dll` beside `ocarina.exe` from the kit's `bin\`. To use another DLSS version, put
   your own `nvngx_dlss.dll` there: later builds keep it.