Are there any LED strip controllers that would allow me to connect a (preferably) small physical capacitative button in the LED strip and program to respond to it in some way (toggle/dim). I would guess this sort of thing would need to be ESPHome based, but Zigbee/Zwave are fine too.
Ideally would be able to control tunable white LED stips, but I’ll take single colour white at this stage.
I believe this Athom device (link below) would allow you to do your own functions with the various types of ‘presses’ you could program for the button on the controller. Make sure to order the ‘tasmota’ version not homekit.
Another thing to consider is the type of LED strips you want to control, this is a RGB only controller. Will not control the ‘smart’ LED strips nor strips with more than RGB, for example 4 or 5 colors strips that include warm and/or bright white. You can still control a bright/warm white strip with no RGB colors, you just plug the warm and bright white lines into say the Red and Green lines.
The challenge with most of the DIY setups is that they do not have cases that will fit well in the ‘significant other acceptance’ spectrum. You can 3D Print enclosures. Another route (read rabbit hole) I went was to find a Tuya based device that was in the SOA spectrum, the challenge with these is that you have to accept the ‘data and control is via Asia’ not all local, or in my case I hacked the device to replace the firmware in it to make it local only control. Second link below is to the warm/bright white Tuya strip I am using. Note, it has three buttons I can program.
I’ve not seen any Zigbee LED strip controllers that offer any buttons on the device controller that you can control. That said, you could easily place a Ikea (or similar) zigbee switch near the strip and control the zigbee LED strip via Zigbee2MQTT or ZHA. I use one of these small Ikea switches to control some under cabinet lights in the kitchen, works very well.
ATHOM pre Flashed Tasmota RGB LED Light Strip Controller 5V-12V
https://www.aliexpress.com/i/3256801908951059.html?gatewayAdapt=4itemAdapt
Tasmota Template
{"NAME":"LS5050C-TAS","GPIO":[32,0,0,0,417,0,0,0,416,0,418,0,0,0],"FLAG":0,"BASE":18}
GPIO
GPIO# Component
GPIO0 Button1
GPIO1 None
GPIO2 None
GPIO3 None
GPIO4 PWM2
GPIO5 None
GPIO9 None
GPIO10 None
GPIO12 PWM1
GPIO13 None
GPIO14 PWM3
GPIO15 None
GPIO16 None
FLAG None
Ustellar 40ft Smart Tunable White Led Strip Light 3000K-6000K App WIFI Cool White Tape Light
And a lesson I learned, don’t keep the LED strip in the roll while you are testing. This is an under appreciated fire starter!
Good hunting!
Thanks! I actually meant a button I can connect and use as an input. My transformer for the led strips is hidden away, and I was going to put the controller there too, and then place a small capacitative button on the strip itself and run 1 m of wire between the two.
I’ve found the Fibaro RGBW 2 which actually has 4 inputs for analogue sensors/buttons, so it sounds like I could use it.
But it doesn’t do cold/warm white. @dproffer since you mention this: is HA smart enough to fake a colour temperature from a cold white connected to R and a warm white connected to W? I would like Adaptive Lighting to change the temp and the physical button to just change the brightnes.
If you can find a ESP based LED strip controller, then with Tasmota, ESPHome or as @TinyDoT indicates WLED can capture input from one or more buttons. And to your need to have the button remote, then it is just up to you to figure out the wiring. The Fibaro device sounds capable as well and offers RGB plus one white channel, I have not done any Zwave stuff in a long while so out of my domain.
To your question about color channels, how the controller and it color and temperature capabilities appear to Home Assistant would probably depend on the software interface/api between the controller and Home Assistant. HA’s three types of light configuration methods offer a lot of options to you configure your specific light, just have plenty of 
and/or 
ready when you sit down to figure it out 
. I’m diddling around with adaptive lighting as well and it can be a bit of a head scratcher with different types of lights. From my experience, the LED controllers have no idea what color LED in on what channel, they just modulate the channel. So it is up to you do the mapping. The ‘smart’ LED strips with the neopixel type LEDs are different story.
For my adventures into light color/temperature, my preference is to have a separate bright white and warm white channel that I can mix. Look for LED strips that offer separately controllable bright and warm channels. In addition, I over do it and play around with mixing the RGB channels with the two whites to ‘in theory’ yield better colors/temperatures. But very subjective.
Good hunting!