Actually add the mediator lmao

Author: tomgeorge

lua/eca/mediator.lua

@@ -0,0 +1,25 @@
+---@class eca.Mediator
+---@field server eca.Server
+local mediator = {}
+
+---@param server eca.Server
+---@return eca.Mediator
+function mediator.new(server)
+  return setmetatable({
+    server = server,
+  }, { __index = mediator })
+end
+
+---@param method string
+---@param params eca.MessageParams
+---@param callback fun(err: string, result: table)
+function mediator:send(method, params, callback)
+  if not self.server:is_running() then
+    print("not running")
+    callback("Server is not running, please start the server", nil)
+    return
+  end
+  self.server:send_request(method, params, callback)
+end
+
+return mediator