refactor: change DEF_EX macro's underlying implementation to template

[shenlebantongying]

Fun stuff :)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[xiaoyifang]

template and extra fmt::format? not easy to understand compared to #define.
the previous version is ok.

[shenlebantongying]

Now it is easier to modify them. Macro don't have types, but template code have some types.

In IDEs, the code can be edited like normal code with inline hints, type warnings...

And there are no warnings anymore.

---

The single line fmt::format is technically better

From

std::string( exDescription ) + " " + value_

to

fmt::format( "{} {}", description, message_ )

One std::string construction and " " concatenation are removed.