feat(auth): add support for persisting disabled flag in token storage

- Updated `FileTokenStore` and related stores (`objectstore`, `gitstore`, `postgresstore`) to include the `disabled` flag in metadata for token storage.
- Adjusted `Auth` metadata handling to initialize empty maps when absent.
- Refined logic in `auto_refresh_loop` and `conductor` to exclude `disabled` tokens from refresh checks.
- Added comprehensive unit tests to verify proper handling of the `disabled` flag in storage and retrieval operations.

sdk/cliproxy/auth/auto_refresh_loop.go

@@ -336,7 +336,7 @@ func (l *authAutoRefreshLoop) remove(authID string) {
 }
 
 func nextRefreshCheckAt(now time.Time, auth *Auth, interval time.Duration) (time.Time, bool) {
-	if auth == nil || auth.Disabled {
+	if auth == nil {
 		return time.Time{}, false
 	}