Would appreciate a guide to integration with codecov.io for non-NEAR projects

[scouten-adobe]

I'd like to generate code coverage for a WASM(*) project that is not using the NEAR framework and post those results to codecov.io.

The README and other documentation says (cryptically) ...

    // Invoke a function to preserve the coverage data or use `println!` for debugging.

... but provides no example for what function to call or where to place the file.

From what I can tell, the result of calling cargo +nightly wasmcov test -- --all-features generates no .profraw files or .lcov files and I can't find any supporting documentation to tell me how to generate those.

Please review the output of the following CI test run (https://github.com/scouten-adobe/TEMP-c2pa-crypto/actions/runs/10513025492/job/29127668743), specifically the "Unit tests (WASM, nightly, code coverage)" job, where I've run the above step and then dumped the contents of the target and wasmcov trees afterwards.

What am I missing?

(*) Also runs on other non-WASM platforms. Coverage reports there are working as intended.