Use closure for defer body
Revert to main
Rework implementation to keep FuncDecl
Add AST briding
Add test with async let
Add main actor tests
Add additional tests
Memory unsafety in the iteration part of the for-in loop (i.e., the part
that works on the iterator) can be covered by the "unsafe" effect on
the for..in loop, before the pattern.
* Instead of hoisting VarDecl in the bridging functions, do it in
ASTGen.
* Introduce `Decl::forEachDeclToHoist` to handle VarDecls in
PatternBindingDecl, and EnumElementDecl in EnumCaseDecl.
* Intorduce `withBridgedSwiftClosure(closure:call:)` as a callback
mechanism between Swift and C++
* In `generate(sourceFile:)`, instead of using `generate(codeBlockItem:)`
handle `CodeBlockItemSyntax.Item` manually to handle `TLCD` wrapping
and `VarDecl` hoisting.
* Make `generate(variableDecl:)` handle TLCD correctly.