Inconsistent credential status enums across 5 credential tables
Imported from GitHub issue El-SaMa/oma#98 by @El-SaMa.
Five separate credential tables (`cpanel_credentials`, `enhance_credentials`, `enhance_db_node_credentials`, `enhance_ssh_settings`, `settings_credentials`) each define their own status vocabulary:
- enhance: `unverified / connected / error`
- cpanel: `connected / error / unknown`
- settings_credentials: `unconfigured / ok / error`
No shared type — every new integration invents a fourth vocabulary.
Fix: define `create type credential_status as enum ('unverified','connected','error')` once and migrate all five tables onto it.