Task: Define and announce community calls for SIG Core

### Understand the Task

**Description**
The goal is to find a good setup for community calls for SIG Core, with a channel, cadence and format and to announce its start

### Any further valuable resources.

_No response_

### What is required to accept the Task as done.

**Done Criteria**
- [ ] Channel, cadence and format defined and published in charter
- [ ] First call announced
