Bug: Harbor User resources fail with external-name annotations

[rossigee]

Problem

Harbor User resources fail when using crossplane.io/external-name annotations:

user_id in path must be of type int64: "testuser"

Root Cause

• Crossplane sets resource ID to username from external-name
• Harbor API requires numeric user IDs: /users/123 not /users/testuser
• Provider lacks username→ID translation

Reproduction

apiVersion: user.harbor.crossplane.io/v1alpha1
kind: User
metadata:
  annotations:
    crossplane.io/external-name: "testuser"
spec:
  forProvider:
    username: testuser
    # ... other fields

Expected

User created successfully with username "testuser"

Actual

422 validation error - Harbor API rejects username in ID field

Solution

Add Upjet external-name configuration to handle username→numeric ID conversion while preserving username-based external names.