Remove linux commands, respect tls_skip_insecure as completionParam and set correct arch on amd64

[badbyte7]

I changed the runCommand part to kotlin/java code, so that the llm-ls download also works under windows, and if curl is not installed (newer Ubuntu verions). It also respects proxy and certificate settings.

In my two tested Ubuntu versions the architecture was amd64, where no llm-ls is available. I added a hardcoded conversion to x86_64.

I also realised, that the llm-ls has a tls_skip_verify_insecure CompletionParameter prepared and the plugin also has the setting, but it was not sent in the completion request to the llm-ls. This setting/parameter will be sent now.

The only thing still open are the proxy settings for the llm-ls. I actually set the https_proxy environment variable before I launch the Idea, but it would be much nicer, if the plugin could do this to. But up to now I could not read the proxy settings of the IDE.

I hope this helps and the quality of the code is ok. ;-)