Fix dropped craftitems/tools not using light_source values (#9438)

builtin/game/item_entity.lua

@@ -54,7 +54,7 @@ core.register_entity(":__builtin:item", {
 		local max_count = stack:get_stack_max()
 		local count = math.min(stack:get_count(), max_count)
 		local size = 0.2 + 0.1 * (count / max_count) ^ (1 / 3)
-		local def = core.registered_nodes[itemname]
+		local def = core.registered_items[itemname]
 		local glow = def and math.floor(def.light_source / 2 + 0.5)
 
 		self.object:set_properties({

doc/lua_api.txt

@@ -7026,6 +7026,13 @@ Used by `minetest.register_node`, `minetest.register_craftitem`, and
 
         liquids_pointable = false,
 
+        light_source = 0,
+        -- When used for nodes: Defines amount of light emitted by node.
+        -- Otherwise: Defines texture glow when viewed as a dropped item
+        -- To set the maximum (14), use the value 'minetest.LIGHT_MAX'.
+        -- A value outside the range 0 to minetest.LIGHT_MAX causes undefined
+        -- behavior.
+
         -- See "Tools" section for an example including explanation
         tool_capabilities = {
             full_punch_interval = 1.0,
@@ -7225,12 +7232,6 @@ Used by `minetest.register_node`.
         drowning = 0,
         -- Player will take this amount of damage if no bubbles are left
 
-        light_source = 0,
-        -- Amount of light emitted by node.
-        -- To set the maximum (14), use the value 'minetest.LIGHT_MAX'.
-        -- A value outside the range 0 to minetest.LIGHT_MAX causes undefined
-        -- behavior.
-
         damage_per_second = 0,
         -- If player is inside node, this damage is caused