bugfix(controlbar): Fix possible divisions by zero in Control Bar code

[Caball009]

• Related issue: Division by zero crash in W3DCommandBarGenExpDraw() when experience points for level up are 0 #797
• Follow-up for PR: [GEN][ZH] Fix possible division by zero in W3DCommandBarGenExpDraw() #810

Using the modified rank file in #797, there are two more places the game would crash because of a division by zero; in ControlBar::populatePurchaseScience and ControlBar::updateContextPurchaseScience.

Issue reproduction steps:

1. Add the modified rank ini data to a custom map.
2. Start a match and click on the special powers menu.
3. Game crashes due to a division by zero.

Callstacks:

generalszh.exe!ControlBar::populatePurchaseScience(Player * player) Line 430
generalszh.exe!ControlBar::showPurchaseScience() Line 2977
generalszh.exe!ControlBar::togglePurchaseScience() Line 3016
generalszh.exe!ControlBarSystem(GameWindow * window, unsigned int msg, unsigned int mData1, unsigned int mData2) Line 418
generalszh.exe!GameWindowManager::winSendSystemMsg(GameWindow * window, unsigned int msg, unsigned int mData1, unsigned int mData2) Line 705
generalszh.exe!GadgetPushButtonInput(GameWindow * window, unsigned int msg, unsigned int mData1, unsigned int mData2) Line 218
generalszh.exe!GameWindowManager::winSendInputMsg(GameWindow * window, unsigned int msg, unsigned int mData1, unsigned int mData2) Line 724
generalszh.exe!GameWindowManager::winProcessMouseEvent(GameWindowMessage msg, ICoord2D * mousePos, void * data) Line 919
generalszh.exe!WindowTranslator::translateGameMessage(const GameMessage * msg) Line 242
generalszh.exe!MessageStream::propagateMessages() Line 1090
generalszh.exe!GameEngine::update() Line 910
generalszh.exe!Win32GameEngine::update() Line 91
generalszh.exe!GameEngine::execute() Line 983
generalszh.exe!GameMain() Line 55
generalszh.exe!WinMain(HINSTANCE__ * hInstance, HINSTANCE__ * hPrevInstance, char * lpCmdLine, int nCmdShow) Line 929

generalszh.exe!ControlBar::updateContextPurchaseScience() Line 495
generalszh.exe!ControlBar::update() Line 1530
generalszh.exe!InGameUI::update() Line 2093
generalszh.exe!W3DInGameUI::update() Line 370
generalszh.exe!SubsystemInterface::UPDATE() Line 131
generalszh.exe!GameClient::update() Line 781
generalszh.exe!W3DGameClient::update() Line 94
generalszh.exe!SubsystemInterface::UPDATE() Line 131
generalszh.exe!GameEngine::update() Line 910
generalszh.exe!Win32GameEngine::update() Line 91
generalszh.exe!GameEngine::execute() Line 983
generalszh.exe!GameMain() Line 55
generalszh.exe!WinMain(HINSTANCE__ * hInstance, HINSTANCE__ * hPrevInstance, char * lpCmdLine, int nCmdShow) Line 929

[greptile-apps]

Greptile Summary

This PR updates rank threshold handling to avoid zero-width progress intervals. The main changes are:

• Normalize zero or equal rank thresholds in both Player implementations.
• Update purchase-science progress calculations.
• Route general experience progress through the normalized player thresholds.

Confidence Score: 5/5

This looks safe to merge.

• No blocking issues found in the changed code.

Important Files Changed

Filename	Overview
Core/GameEngine/Source/GameClient/GUI/ControlBar/ControlBar.cpp	Makes the purchase-science progress locals immutable while retaining the existing calculation.
Core/GameEngineDevice/Source/W3DDevice/GameClient/GUI/GUICallbacks/W3DControlBar.cpp	Uses the player rank interval directly for general experience progress rendering.
Generals/Code/GameEngine/Source/Common/RTS/Player.cpp	Normalizes invalid rank thresholds during rank reset and rank changes.
GeneralsMD/Code/GameEngine/Source/Common/RTS/Player.cpp	Mirrors the rank threshold normalization for the Zero Hour player implementation.

_{Reviews (6): Last reviewed commit: "bugfix(controlbar): Fix possible divisio..." | Re-trigger Greptile}

[Skyaero42]

If skillPointsRequired is 0, than this implies that a rank up didn't go through - after all the player has enough points to rank up to the next level. So I wonder if the fix is at the wrong place

[xezon]

This code now exists at 3 locations. Maybe consolidate it to one?

[xezon]

I wonder if this should be even a bit smarter and set progress to zero if the max skill points have been reached. Currently It looks like getSkillPointsLevelUp will become INT_MAX after the last level so it is not totally clean.

[Caball009]

Not sure if the new implementation is any better.

[xezon]

Check the bot complaints first.

[Caball009]

@greptileai re-review this pull request.