pub fn make_cmd20106_symbol(market: i32, code: &str) -> Option<String>Expand description
Build backend CMD 20106 SecuritiesReq.symbols entry from FTAPI market+code.
Ref: moomoo
Src/FTQuant/Src/FTQuantServer/APIProto_StockInfoReq.cpp:487-550
MakeReqSymbol.
Most securities are "CODE.SUFFIX", but plate/list codes are special:
LIST* is converted to BK*, and existing BK* codes are sent without
suffix. That mirrors C++ instead of treating every user code as a plain
exchange symbol.