move from profile to profile with accounts

common/proto/accounting.proto

@@ -433,6 +433,25 @@ message OpeningBalanceAccountMapping {
   string created_by_user_id = 14;
 }
 
+// A predecessor account still holding value that no mapping carries into the
+// target period. Closing the target period drops these balances silently, so
+// each one is either an account left to map or one deliberately closed out.
+message UnmappedSourceAccount {
+  int64 source_period_id = 1;
+  string source_profile_name = 2;
+  repeated string source_account_segments = 3;
+  string currency = 4;
+  // Signed balance uses the debit-positive convention, and is never zero.
+  string closing_balance = 5;
+  OpeningBalanceStatus status = 6;
+}
+
 message ListOpeningBalanceAccountsResponse {
   repeated OpeningBalanceAccountMapping mappings = 1;
+
+  // Empty while the target period still inherits every predecessor balance by
+  // account path. Populated once the period carries balances by explicit
+  // mapping only, which happens when the predecessor belongs to another
+  // profile or when the period has at least one mapping of its own.
+  repeated UnmappedSourceAccount unmapped_source_accounts = 2;
 }