Undefined reference to `app_main'

When trying to create a blank project, I always get undefined reference to 'app_main'. When I select Arduino as framework it works but not with idf. Maybe it is because of the new idf 5.X version? If yes, how to change that during project setup?

Can you pload your project files? (Without .pio folder)

Using VS Code Version: 1.80.1 (Universal)
Platformio: Core 6.1.9 Home 3.4.4

Can you replace the contents of the src/CMakeLists.txt with

idf_component_register(SRCS "main.c"
                    INCLUDE_DIRS ".")


Sadly gives me the same error:

/esp/esp-idf/components/freertos/port/port_common.c:135: undefined reference to `app_main'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.