Add "button dance" info on first install.

[jonwaterschoot]

Which doc or page?

https://github.com/engmung/Patternflow/blob/main/BUILD_GUIDE.md#8-firmware

What is wrong or missing?

In both the build guide as well as the modal that steps you through the upload / flash settings we should add the correct button presses to enter the flashing mode.
In the Online flashing modal there's already a screen for when the user clicks / cancels out of the popup that shows good debug steps:

No port selected
If you didn't select a port because you didn't see your device listed, try the following steps:
Make sure that the device is connected to this computer (the one that runs the browser that shows this website)
Most devices have a tiny light when it is powered on. If yours has one, make sure it is on.
Make sure that the USB cable you use can be used for data and is not a power-only cable.
Make sure you have the right drivers installed. Below are the drivers for common chips used in ESP devices:
CP2102 drivers: Windows & Mac
CH342, CH343, CH9102 drivers: Windows, Mac
(download via blue button with icon)
CH340, CH341 drivers: Windows, Mac
(download via blue button with icon)

Suggested fix

Before the first step we should already say: if you do not see USB JTAG/serial debug unit in the popup, try pressing the boot + reset buttons like this:
To manually force an ESP32-S3 into firmware download (bootloader) mode:

1. Press and hold the BOOT button,
2. tap and release the EN / RST(Reset) button,
3. and then release the BOOT button.

You should now see the option with this line in it: USB JTAG/serial debug unit (COM4) – Paired
(The COM port number will depend on which USB port you use on your computer.)

[engmung]

Thanks for flagging all of these!

1. Added the BOOT/RST steps to the build guide and next to the flash button. Looking into the driver part, it turned out to be a non-issue — uploads used to go through the right port, but they go through the left one now, and that one doesn't need CH34x or CP210x at all. The chip does USB itself so Windows just picks it up. Trimmed that section down to a single line saying exactly that, since the flasher still shows those driver links and they don't apply on this port.

2. This one seems to vary by machine and I couldn't reproduce it here. The flasher waits about 10s for the device to answer after flashing and just moves on if it doesn't, and how fast USB comes back differs per host. I bumped the wait to 20s, but it's not really something I can control from my side. If it happens again let me know. Also you don't need to reflash to set Wi-Fi — just open the flasher again and it'll offer it.

3. The single pattern is intentional for now. I pulled the presets out so people land on the community and pick up the deck flow. The site still saying 34 was just wrong though, that's fixed. The other 33 are the Basics pack at community.patternflow.work/community/decks, one click. I might bake some presets back in later, still thinking about it.

No need to open separate issues, closing this one. Thanks again!