fix(windows): use GetTickCount64 to prevent overflow after 49.7 days

[TimeToBuildBob]

Summary

• GetTickCount returns a 32-bit DWORD that wraps at 2^32 ms (~49.7 days of uptime)
• After wrapping, the idle time calculation produces incorrect results
• Switched to GetTickCount64 which returns a 64-bit value with no practical overflow
• Added wraparound handling for dwTime from GetLastInputInfo (always 32-bit per Windows API)

Technical details

The seconds_since_last_input() function computed GetTickCount() - dwTime. After 49.7 days:

• GetTickCount() wraps to near 0
• dwTime (last input) could still be a large number
• Result: negative value (displayed as huge idle time)

The fix uses GetTickCount64() and compares only the lower 32 bits against dwTime, handling the wrap edge case.

Note: GetTickCount64 requires Windows Vista+ (2007), which should be a safe baseline in 2026.

Test plan

• Cannot run on Linux, but the change is minimal and follows the Microsoft documentation for GetTickCount64
• The overflow handling logic is straightforward: mask to 32 bits, handle wrap

Fixes #16

---

Important

Switches to GetTickCount64 in aw_watcher_afk/windows.py to prevent overflow after 49.7 days and handles dwTime wraparound.

• Behavior:
  • Replaces GetTickCount with GetTickCount64 in aw_watcher_afk/windows.py to prevent overflow after 49.7 days.
  • Handles wraparound for dwTime from GetLastInputInfo in seconds_since_last_input().
• Functions:
  • Adds _getTickCount64() to retrieve 64-bit tick count.
  • Modifies seconds_since_last_input() to use 64-bit tick count and handle 32-bit wraparound.
• Misc:
  • Requires Windows Vista+ for GetTickCount64.

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[greptile-apps]

Greptile Summary

This PR fixes a critical bug where GetTickCount() overflows after 49.7 days of system uptime, causing incorrect idle time calculations. The fix switches to GetTickCount64() which returns a 64-bit value with no practical overflow risk.

Key Changes:

• Replaced 32-bit GetTickCount() with 64-bit GetTickCount64() in _getTickCount64() function
• Added wraparound handling for the 32-bit dwTime value from GetLastInputInfo() API
• Compares lower 32 bits of 64-bit tick count against 32-bit last input tick to detect wraparound
• Calculates time difference correctly across the 32-bit boundary

Implementation Notes:

• The wraparound logic assumes at most one 32-bit wrap since last input (handles up to 49.7 days of inactivity)
• Requires Windows Vista+ (2007), which is a safe baseline in 2026
• The fix follows Microsoft's recommended approach for handling mixed 32/64-bit tick counts

Confidence Score: 5/5

• This PR is safe to merge with no risk - it fixes a critical overflow bug with a well-tested Windows API approach
• The fix is minimal, focused, and follows Microsoft's documented approach for GetTickCount64. The wraparound handling logic is correct for typical usage (assuming wraparound occurs at most once). The change has no impact on other platforms and requires Windows Vista+ which is universally available in 2026.
• No files require special attention

Important Files Changed

Filename	Overview
aw_watcher_afk/windows.py	Replaces GetTickCount with GetTickCount64 to fix overflow after 49.7 days, adds wraparound handling for 32-bit dwTime from GetLastInputInfo

_{Last reviewed commit: 44b9ff6}

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