This commit updates the documentation for the WASM examples to include a
note about the generation of the `worker.js` file. As of Emscripten
3.1.58 (April 2024), separate worker.js files are no longer generated
and the worker is embedded in the main JS file.
The motivation for this change is to inform users about the new behavior
of Emscripten and why the `worker.js` file may not be present.
Refs: https://github.com/ggml-org/whisper.cpp/issues/3123
This commit updates the README files for the wasm examples to include
instructions on how to run the examples using the provided server.py
which was included in Commit 6e8242f7fe
("examples : command.wasm updates (#2904)").
The motivation for this is consistency with the command.wasm example.
