improvement(util): wrap Retry last error with %w for error chain pres…

[mdryaan]

Description

util.Retry in util/common.go (line 220) used %s as the verb when wrapping the last error in the final fmt.Errorf call. This converts the error to a plain string, permanently discarding its type. Any caller using errors.Is or errors.As on a util.Retry return value would always get false, making it impossible to inspect or match the underlying cause. Changing %s to %w makes the error chain available to callers without any behaviour change at runtime.

Fixes #380

How Has This Been Tested?

util/common.go line 220 changed from %s to %w. go build ./... passes. The pre-existing make vet and make unit-test failures (undefined: util.Client, unknown field ClusterName) exist on master before this branch and are unrelated to this change.

Checklist:

• The title of the PR states what changed and the related issues number (used for the release note).
• Does this PR requires documentation updates? — No.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have tested it for all user roles.
• I have added all the required unit test cases.