Add server user management commands

notes/PHASE_4_COVERAGE_NOTES.md

@@ -15,7 +15,7 @@ go test -cover ./...
 Current default coverage snapshot after Phase 4 implementation:
 
 ```text
-internal/app       64.3%
+internal/app       65.3%
 internal/backup    42.3%
 internal/config    79.5%
 internal/dbutil     8.6%
@@ -62,6 +62,7 @@ Default tests now cover:
 - MySQL identifier quoting and duplicate-column detection
 - Git utility behavior with temp bare repos
 - CLI parsing, dispatch errors, human-readable output, and JSON opt-ins
+- Direct server user management parsing and DB operations
 - CLI HTTP workflows for auth, repos, PRs, tokens, admin, and storage checks
 - API auth handlers, token handlers, admin handlers
 - Repository create/get/search/update/delete/fork/collaborator flows