With these requirements, you are alone with the wrong product. As soon as you pyhiscally interrupt the circuit (at the switch itself), you will no longer be able to switch on the light with the app until you press the switch again. What you need is an app-enabled LAMP with a built-in dimmer. I have the Xiaomi Mi, for example, which would work. Go to "table lamps", filter for "dimmable with built-in controller" and your smart home (Google, Alexa, Siri...), then you're right :)

Dimming, colour temperature and switching on/off via the app already works. But as @andyhaeusler wrote: once disconnected from the power supply with the switch, the lamp must also be switched on again with the switch.
However, this compromise works very well for me. I always switch on some lamps with the switch, others via the app. WiZ also knows different switch-on behaviours: "last status" or "WiZclick" (with different pre-sets).
Switching off via the switch also offers zero-standby consumption.