add a __tostring method to every object (#1534)

* added a stupid __tostring to every object

* moved every __tostring to just after the :extend() call

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Co-authored-by: Adam <adamdharrison@gmail.com>
(cherry picked from commit 880e7f1fa1521cdf176f44627a27c901e187058e)

data/core/node.lua

@@ -9,6 +9,8 @@ local View = require "core.view"
 ---@class core.node : core.object
 local Node = Object:extend()
 
+function Node:__tostring() return "Node" end
+
 function Node:new(type)
   self.type = type or "leaf"
   self.position = { x = 0, y = 0 }