When logged in to Kiro IDE as an organization (AWS IAM Identity Center),
token import fails because IDC tokens require clientId/clientSecret for
refresh and use a different profileArn than social/builder-id accounts.
Changes:
- auto-import: read clientId/clientSecret from SSO cache client registration
file, read profileArn from Kiro IDE profile.json, normalize ARN region
- import: accept IDC credentials, use KiroService.refreshToken with them,
persist credentials for future automatic refreshes
- KiroAuthModal: pass IDC credentials from auto-detect through to import
Co-authored-by: Cursor <cursoragent@cursor.com>
