Fixes#1346 by creating an overlay for go/build/build.go that sets
Compiler to "gc" in defaultContext(). This allows user code using
go/build package to work with llgo while preserving runtime.Compiler
as "llgo" for identification purposes.
The overlay replaces the entire go/build/build.go file with a modified
version where line 342 changes from 'c.Compiler = runtime.Compiler' to
'c.Compiler = "gc"'. This minimal change ensures go/build recognizes
llgo-compiled binaries without requiring changes to user code.
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Co-authored-by: luoliwoshang <luoliwoshang@users.noreply.github.com>
