Harden anti-exploit tamper detection against function interception

[realmaitreal]

Changes to MainModule/Client/Core/Anti.luau

Rationale

The existing tamper detection loop relied on calling debug.info(Detected, ...) to
verify that Detected had not been modified. This approach can be neutralised by
intercepting debug.info at the environment level, causing the tamper loop to stall
indefinitely. Additionally, while true do end was used as a response to detected
tampering, which Roblox kills via script timeout — rendering enforcement ineffective.

Changes

• Capture debug.info as a local (rawDebugInfo) before setfenv alters the
  environment, preserving a direct reference to the original C function independent
  of later environment-level changes.
• Capture Kill's debug metadata (source, line, name) at module load time for
  later integrity comparison.
• Replace all tamper-sensitive debug.info calls in checkStack, isMethamethodValid,
  and the xpcall error handlers with rawDebugInfo.
• Add a private behavioral heartbeat counter (_heartbeatSeq) incremented by the real
  Detected body when called with action "_". The tamper loop checks this counter
  to verify Detected is executing its actual implementation, rather than relying solely
  on debug.info introspection of Detected (which can be intercepted).
• Add an integrity check for Kill by comparing its current debug.info metadata
  against the snapshot taken at load time.
• Replace all while true do end enforcement responses with the proper
  Detected(...) + pcall(Disconnect, ...) + pcall(Kill, ...) + pcall(Kick, Player, ...)
  chain already used elsewhere in the file. while true do end is killed by Roblox's
  script timeout and provides no actual enforcement.

[realmaitreal]

I'm currently working on more tamper detection.

[realmaitreal]

Added a load-time debug metadata snapshot of Detected and Kill, checked each tamper loop iteration via a pre-setfenv reference to debug.info. Since hookfunction mutates function objects in-place and changes their debug metadata, any hook is caught without calling Detected, defeating bypasses that pass the heartbeat sentinel through to the original.

[GalacticInspired]

@Expertcoderz @coasterteam