added os detection to use powershell in windows instead of cmd

init.lua

@@ -3,7 +3,7 @@ require("config.lazy")
 
 require("typst-preview").setup({
 	-- This function will be called to determine the root of the typst project
-	get_root = function(path_of_main_file)
+	get_root = function()
 		local root = os.getenv("TYPST_ROOT")
 		if root then
 			return root
@@ -13,3 +13,18 @@ require("typst-preview").setup({
 })
 
 vim.opt.expandtab = false
+
+--OS detection
+local mySysname = vim.loop.os_uname().sysname
+local isMac = mySysname == "Darwin"
+local isLinux = mySysname == "Linux"
+local isWin = mySysname:find("Windows") and true or false
+local isWsl = isLinux and vim.loop.os_uname().release:find("Microsoft") and true or false
+--Set shell
+if isWin then
+	if vim.fn.executable("pwsh") == 1 then
+		vim.opt.shell = "pwsh" --"pwsh" for 7.x if installed
+	else
+		vim.opt.shell = "powershell" --"powershell" for 5.x
+	end
+end