cad/openvsp: Update to 3.43.1

ChangeLog:
https://openvsp.org/blogs/announcements/2025/07/03/openvsp-3-43-1-released

Features:

• Plain flap airfoil modification

Library Updates:

• Update Code-Eli to fix FindThickness

Build System:

• Update GitHub Windows build to windows_2022 runner

Fixes:

• Fix large scale MultiFacade problem
• Fix Calculix element numbering
• Fix Watermark display
• Fix fscanf buffer overflows
• Fix FindThickness — used by airfoil TE trimming by thickness
• Fix BOR file load

MFH: 2025Q3 (possible security risk due to buffer overflow)
(cherry picked from commit 5ee3814e0bd80cd1ffc0adec43c893d4654bbae1)