Update V-HACD library to version 4.1

[madmiraal]

Fixes build errors caused by missing #include stdint.h in old version of V-HACD:

In file included from thirdparty/vhacd/src/vhacdICHull.cpp:15:
thirdparty/vhacd/inc/vhacdICHull.h:46:31: error: unknown type name 'uint32_t'
    ICHullError Process(const uint32_t nPointsCH, const double minVolume = 0.0);
                              ^
thirdparty/vhacd/inc/vhacdICHull.h:76:24: error: unknown type name 'uint32_t'
    bool CleanVertices(uint32_t& addedPoints);
                       ^
thirdparty/vhacd/inc/vhacdICHull.h:80:18: error: unknown type name 'uint32_t'
    bool CleanUp(uint32_t& addedPoints);
                 ^
thirdparty/vhacd/src/vhacdICHull.cpp:56:5: error: unknown type name 'uint32_t'
    uint32_t addedPoints = 0;
    ^
thirdparty/vhacd/src/vhacdICHull.cpp:174:35: error: unknown type name 'uint32_t'
ICHullError ICHull::Process(const uint32_t nPointsCH,
                                  ^
thirdparty/vhacd/src/vhacdICHull.cpp:177:5: error: unknown type name 'uint32_t'
    uint32_t addedPoints = 0;
    ^
thirdparty/vhacd/src/vhacdICHull.cpp:585:22: error: unknown type name 'uint32_t'
bool ICHull::CleanUp(uint32_t& addedPoints)
                     ^
thirdparty/vhacd/src/vhacdICHull.cpp:629:28: error: unknown type name 'uint32_t'
bool ICHull::CleanVertices(uint32_t& addedPoints)

Includes patches submitted upstream to fix a compilation warning and a compilation error:

• Remove unused variable count from ThreadPool kmammou/v-hacd#151
• Fix CostTask t shadowing Timer t kmammou/v-hacd#153

Which fix:

• private field 'count' is unused in ThreadPool kmammou/v-hacd#148:

./thirdparty/vhacd/include/VHACD.h:5698:9: warning: private field 'count' is not used [-Wunused-private-field]
 5698 |     int count;
      |         ^

• In PerformConvexDecomposition(), CostTask t shadows Timer t kmammou/v-hacd#152:

In file included from modules/vhacd/register_types.cpp:35:
./thirdparty/vhacd/include/VHACD.h: In member function 'void VHACD::VHACDImpl::PerformConvexDecomposition()':
./thirdparty/vhacd/include/VHACD.h:7610:38: error: declaration of 't' shadows a previous local [-Werror=shadow=local]
 7610 |                             CostTask t;
      |                                      ^
./thirdparty/vhacd/include/VHACD.h:7546:23: note: shadowed declaration is here
 7546 |                 Timer t;
      |                       ^

Fixes: godotengine/godot#29971

[DanielaOrtner]

Nice to see fixes coming through :)