M-Bus support

**Describe the problem you have/What new integration you would like**
I have a energy meter installed in my house that exposes its data via M-Bus. I would like to see support for reading values over M-Bus. Since M-Bus, supposedly, is used for many kinds of utility meters this might be useful to a lot of people in Europe.
I'm looking for some guidance on how to continue. I'm a bit lost or stuck. If anyone has some input or

**Please describe your use case for this integration and alternatives you've tried:**
I want to enable users to easily add new components for M-Bus meters.

Using M-Bus Master hardware ([MIKROE-3880](https://www.mikroe.com/m-bus-master-click) looks promising, or [DIY version](https://github.com/rscada/libmbus/tree/master/hardware)) and code supporting communication with M-Bus like [libmbus](https://github.com/rscada/libmbus). Adding support for a new meter should be limited to implementing the [manufacturers protocol](https://gavazzi.se/app/uploads/2020/11/em111_em112_m1_cp.pdf).

Alternatives:
I have not tried anything else.

**Additional context**
[Wikipedia says](https://en.wikipedia.org/wiki/Meter-Bus)
_M-Bus or Meter-Bus is a European standard (EN 13757-2 physical and link layer, EN 13757-3 application layer) for the remote reading of water, gas or electricity meters. M-Bus is also usable for other types of consumption meters, such as heating systems or water meters. The M-Bus interface is made for communication on two wires, making it cost-effective. A radio variant of M-Bus Wireless M-Bus is also specified in EN 13757-4._

_The M-Bus was developed to fill the need for a system for the networking and remote reading of utility meters, for example to measure the consumption of gas or water in the home. This bus fulfills the special requirements of remotely powered or battery-driven systems, including consumer utility meters. When interrogated, the meters deliver the data they have collected to a common master, such as a hand-held computer, connected at periodic intervals to read all utility meters of a building. An alternative method of collecting data centrally is to transmit meter readings via a modem._

_Other applications for the M-Bus such as alarm systems, flexible illumination installations, heating control, etc. are suitable._

No project files or tests are named. Start by reviewing libmbus and the MIKROE-3880 or DIY master hardware, then compare their communication support with the cited manufacturer protocol PDF. Done would require a defined way for users to add M-Bus meters and demonstrated reading of the requested meter values.

Written by the indexing model from the issue text.