[vscode-mlir] Add support for restarting the server on setting/server changes

This revision adds detection for changes to either the mlir-lsp-server binary or the setting, and prompts the user to restart the server. Whether the user gets prompted or not is a configurable setting in the extension, and this setting may updated based on the user response to the prompt.

Differential Revision: https://reviews.llvm.org/D104501