[SURE-9488] Fleet UI errors will simplify troubleshooting and reduce escalations

[kkaempf]

SURE-9488

Request Description: Descriptive Error Messages in the Fleet UI

###v Expected behaviour: UI should provide more descriptive error messages where you can pinpoint where the issue is since Hosted Rancher logs are not accessible. Or allow viewing the Rancher logs in the UI

*Actual behaviour: *The message show like 'failed: 3/1time="2024-11-28T09:04:55Z" level=fatal msg="context canceled"' where it doesn't provide useful context where to check the issue.

*Actual issue: *fleet.yaml contains duplicate key entry and validation fails or sometimes the helm chart doesn't exist.

[manno]

Let's check all the error conditions and add a "context", like "error in gitjob: ".
Maybe strip or format the timestamp, too.
Replace context canceled with timeout?

This probably translates into "timeout waiting for gitjob to complete"