GUI: Clock Timer in WebServer?

**Describe the problem you have/What new integration you would like**
I would love to schedule a Start and Stop Time thru the webserver of ESPHome.
E.g.
Select the weekdays
Select the weeks
Select the month
Select Start Time
Select Stop Time

So more or less a graphical UI what translates into the givens of on_time trigger
https://esphome.io/components/time/index.html#on-time-trigger

**Please describe your use case for this integration and alternatives you've tried:**

I want to create a ESPHome based PoolManager.
A pool outside of your house does have some critical aspects:
- Not always in wifi range
- The ESPHome Device should run even if wifi or HA is missing

So to say:
The measurements of ORP, PH and its controlling of chlorid and PH must safely run without any external dependcies.

**Additional context**

Here is what I try to do from hardware perspective:

The Tuya W2839 is just the measuring part and connected to the ESP by serial (RX/TX/GND)

The ESP is a device with 4 Relays and 8 GPIO inputs from rocketcontroller.com

https://rocketcontroller.com/product/astra-controller-4-relays-16a-8-gpio-input-dc-power-led-br4g8al/

With these I would like to control my Pool chemistry.
Means the Chlorid and PH value as well as the run time of the SFA and heat pump.


If there is any possibility that you consider implementing the WebServer "Timer Clock" feature, this would be great and appreciated.
I would even donate some amount to supporting this.

Thanks & BR
Chris

Start by reviewing the ESPHome WebServer feature area and the documented on_time trigger linked in the issue. Define how weekday, week, month, start-time, and stop-time selections should map to scheduling, including operation without Wi-Fi or Home Assistant. Done means the WebServer exposes a usable timer configuration that reliably controls the requested device actions offline.

Written by the indexing model from the issue text.