Improve error handling for missing nested headers in lite

[anutosh491]

1. If we expect a header in the file system but that's not there we're good and we catch it , for example

2. But if we have X.h depend on a Y.h and Y.h is missing, we're a bit lost.

Consider this scenario

To run xsimd, we need wasm_simd128.h. Let's say I do not add it on purpose, I see this

[anutosh491]

Why this might be a xeus-cpp/cppinterop error ?

I see llvm and clang-repl doing their job here !

If I replicate the above case on my toy project (no xeus/xeus-cpp/cppinterop influence just llvm)

https://github.com/anutosh491/clang-repl-wasm, I see

Which means we're capturing the error

/include/wasm_simd128.h:10:15: fatal error: 'wasm_simd128.h' file not found
   10 | #include_next <wasm_simd128.h>
      |               ^~~~~~~~~~~~~~~~

Along with

Aborted(Assertion failed: getPtr() && "getFETokenInfo on an empty DeclarationName!", at: /home/runner/work/recipes/recipes/output/bld/rattler-build_llvm_1747412717/work/clang/include/clang/AST/DeclarationName.h,503,getFETokenInfo)

We need to have the stack trace for the error in the notebook itself (and not in the console).
At this point I am guessing we're probably losing the file not found error in the xeus-cpp build or the cppinterop side module build. (probably some emscripten flag during the build somewhere helps ?)

[anutosh491]

This should be addressed once this PR is picked up in the next release

llvm/llvm-project#142445

[anutosh491]

As the above PR was merged, we have no more issues while catching errors related to missing nested headers