* [DNM](decimal) use new way for decimal arithmetic precision promotion
* [improvement](decimal) [DNM](decimal) use new way for decimal arithmetic precision promotion
1. [DNM](decimal) use new way for decimal arithmetic precision promotion
2. throw exception if it overflows for decimal arithmetics
3. throw exception if it overflows when casting among number types
* fix compile error of gcc
* improvement
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Co-authored-by: morrySnow <morrysnow@126.com>