Fix getPedTask crash with invalid primary task index

[HeresHavi]

Summary

Added bounds validation to CTaskManagerSA::GetTask.

Primary task indices outside the valid 0 to 4 range now return nullptr, causing getPedTask to return false safely.

Motivation

The primary task reader used the provided index directly on a five-entry native array. Larger values could read nearby fields and treat them as task pointers, eventually causing an access violation.

For example, a resource might loop through task slots to check what a ped is doing, but accidentally query slot 11. Instead of returning false, the client could interpret the ped pointer stored after the task arrays as a task and crash.

Crash Stack

Exception: Access violation
Module: client.dll
Module offset: 0x00107338
Requested primary task index: 11

CStaticFunctionDefinitions::GetPedTask (CStaticFunctionDefinitions.cpp:1732)
CLuaPedDefs::GetPedTask (CLuaPedDefs.cpp:555)
luaD_precall
luaV_execute
luaD_call
lua_pcall

Test plan

Runtime

• Before Fix: Requesting primary task index 11 caused an access violation in CStaticFunctionDefinitions::GetPedTask.
• After Fix: The same index returned false, and the client stayed open.
• Valid Case: Primary task index 3 returned false for an empty valid slot.
• Invalid Cases: Primary task indices 5 and 10 returned false without an assertion or crash.

Builds and Tests

• Debug | Win32: Game SA project build passed.

Checklist

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