add Lua sandbox with timer system (milestones 1-5 complete)

sandbox-test/scripts/test_metatable_protected.lua

@@ -0,0 +1,33 @@
+-- Test that metatables are protected from manipulation
+
+-- Test 1: String metatable should return protection value, not actual metatable
+local mt = getmetatable("")
+if mt ~= "string" then
+    error("FAIL: string metatable should return 'string', got " .. tostring(mt))
+end
+
+-- Test 2: Cannot add new globals
+local ok, err = pcall(function()
+    _G.my_new_global = "test"
+end)
+if ok then
+    error("FAIL: Should not be able to add new globals")
+end
+
+-- Test 3: Cannot modify existing globals
+local ok2, err2 = pcall(function()
+    _G.print = nil
+end)
+if ok2 then
+    error("FAIL: Should not be able to modify print")
+end
+
+-- Test 4: Cannot replace math table
+local ok3, err3 = pcall(function()
+    _G.math = {}
+end)
+if ok3 then
+    error("FAIL: Should not be able to replace math")
+end
+
+print("PASS: Metatables protected")