Updates the GolangCI linting configuration to allow parallel 
runners, improving performance during linting. Sets a timeout 
of 5 minutes for running checks to ensure they complete in a 
timely manner.

Upgrades the golangci-lint version in the CI configuration to 
ensure compatibility with recent linting features and 
improvements. This change enhances the linting process 
by utilizing the latest version available.

Change the Go Docker image from `golang:1.24.0` to 
`amd64/golang:1.24.0` to ensure compatibility 
with the architecture requirements of the project.

Replace instances of FakeExternalEvent with eventsourced.ExternalEvent 
to standardize event handling. Update tests to reflect changes in 
event structure and improve error reporting. Adjust JSON unmarshaling 
for optimized performance and compatibility with new event type. 
These changes enhance the clarity and maintainability of the code.