feat: use lsp settings to configure custom biome binary

[luckydye]

Closes #18

With this PR the biome binary used by the extension can be configured in the zed settings like this:

{
  "lsp": {
    "biome": {
      "binary": {
        "path": "~/biome/target/debug/biome",
        "arguments": ["lsp-proxy"]
      }
    }
  } 
}

Then the logs will print something like the following:

2024-05-28T01:11:04+02:00 [INFO] starting language server. binary path: "~/biome/target/debug/biome", working directory: "<project>", args: ["lsp-proxy"]

[ematipico]

Could you please update the contribution guide with an example of how a developer can set it up?