Update the README pointing to wasm-wasi-component

[ac000]

Point people to the new wasm-wasi-component language module, but be upfront about its current limitations.

[avahahn]

I like the warnings about the performance limitations (until we fix them at least) but as a potential user I am not sure what I am being warned from in your statement about the rust ecosystem. I am also not sure what you are comparing it to.

Perhaps the warnings concerning performance limitations we can back up with data are worth keeping but I wonder if we can do without the concern about the rust ecosystem.

[ac000]

I suppose the first warning is about the following

1. Some people may rather not install all the rust stuff on their system (I'm not hugely keen myself!), much like they would rather not install all the java stuff, golang stuff etc and that applies to cargo as well, (my ~/.cargo directory is currently 1.4GiB in size). Thankfully Fedora has everything needed packaged up and I don't need to use the dangerous pipe random stuff from the Internet to the shell command...

2. When building the wam-wasi-component module, it downloads and builds nearly 300 crates! and takes 5-7 minutes. I did a cargo clean in the wam-wasi-component directory the other day and it removed > 3.5GiB of stuff. In my view both of those are excessive...

3. I can't even build the wasm-wasi-component model in my standard 512MiB VMs due to OOM, My main Fedora workstation is OK, but whenever I try to build it in say one of my Debian VMs, it fails the first time (because I forgot it needs more RAM) and need to restart it with more memory allocated and try again...

[lcrilly]

These read to me more like prerequisites and system requirements than warnings. Install the toolchain, have enough disk space, have enough memory.