fix: invoke attach callback on main thread

lua/codemp/buffers.lua

@@ -57,7 +57,9 @@ local function attach(name, opts)
 
 	vim.api.nvim_set_option_value('fileformat', 'unix', { buf = buffer })
 	vim.api.nvim_buf_set_name(buffer, name)
+
 	CODEMP.workspace:attach(name):and_then(function (controller)
+		vim.schedule(function()
 			-- TODO disgusting! but poll blocks forever on empty buffers...
 			if not opts.nowait then
 				local promise = controller:poll()
@@ -189,6 +191,7 @@ local function attach(name, opts)
 			print(" ++ attached to buffer " .. name)
 			require('codemp.window').update()
 		end)
+	end)
 end
 
 ---@param buffer? integer if provided, sync given buffer id, otherwise sync current buf