[SAOC 2025] Separate Semantic Routines from AST Nodes Weekly Update #5

[Mohamed El Shorbagy]

# Summary of Progress (October 13 - October 20)

This week was about finding indirect semantic dependencies in AST 
files. For instance, `expression.d` was depending on `ctfeexpr`, 
which relies on some semantic functions. This particular instance 
was refactored in [this merged 
PR](https://github.com/dlang/dmd/pull/21991).

The work continued with other files such as `mtype`. See the 
first [PR](https://github.com/dlang/dmd/pull/22005) to move 
`Type.hasUnsafeBitPatterns` to `typesem` as part of an effort to 
remove the import of `dsymbolsem.size`. Additionally, another 
[PR](https://github.com/dlang/dmd/pull/22007) moves 
`AggregateDeclaration.makeNested` and 
`AggregateDeclaration.makeNested2` to `dsymbolsem`, as they rely 
on the function `Type.alignment`, which in turn depends on 
`dsymbolsem.size`, making this change convenient.

There are some other minor PRs, such as [this 
one](https://github.com/dlang/dmd/pull/22006) to remove an unused 
`ctfeexpr` import from `hdrgen`, and [this 
one](https://github.com/dlang/dmd/pull/21998), which was a fix 
for a previous PR.