[Clang][CWG1815] Support lifetime extension of temporary created by aggregate...

[Clang][CWG1815] Support lifetime extension of temporary created by aggregate initialization using a default member initializer (#87933)

This PR complete [DR1815](https://wg21.link/CWG1815

) under the guidance
of `FIXME` comments. And reuse `CXXDefaultInitExpr` rewrite machinery to
clone the initializer expression on each use that would lifetime extend
its temporaries.

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Signed-off-by: yronglin <yronglin777@gmail.com>