bambu-studio: fix build with gcc15

- add patch from merged upstream PR:
https://www.github.com/bambulab/BambuStudio/pull/8555
https://github.com/bambulab/BambuStudio/commit/434752bf643933f22348d78335abe7f60550e736

Fixes build failure with gcc15:
```
/build/source/src/mcut/source/math.cpp:660:15: error: 'uint32_t' does
not name a type
  660 |         const uint32_t N = polygon_vertices.size();
      |               ^~~~~~~~
/build/source/src/mcut/source/math.cpp:25:1: note: 'uint32_t' is
defined in header '<cstdint>'; this is probably fixable by
adding '#include <cstdint>'
   24 | #include <algorithm> // std::sort
  +++ |+#include <cstdint>
   25 | #include <cstdlib>
/build/source/src/mcut/source/math.cpp:661:20: error: 'N' was not
declared in this scope
  661 |         out.resize(N);
      |                    ^
/build/source/src/mcut/source/math.cpp:669:13: error: 'uint32_t' was not
declared in this scope
  669 |         for(uint32_t i =0; i < N; ++i)
      |             ^~~~~~~~
/build/source/src/mcut/source/math.cpp:669:13: note: 'uint32_t' is
defined in header '<cstdint>'; this is probably fixable by
adding '#include <cstdint>'
```

pkgs/by-name/ba/bambu-studio/package.nix

@@ -3,6 +3,7 @@
   lib,
   binutils,
   fetchFromGitHub,
+  fetchpatch,
   cmake,
   ninja,
   pkg-config,
@@ -121,6 +122,13 @@ stdenv.mkDerivation (finalAttrs: {
     ./patches/no-cereal.patch
     # Cmake 4 support
     ./patches/cmake.patch
+    # Fix build with gcc15
+    # https://github.com/bambulab/BambuStudio/pull/8555
+    (fetchpatch {
+      name = "bambu-studio-include-stdint-header.patch";
+      url = "https://github.com/bambulab/BambuStudio/commit/434752bf643933f22348d78335abe7f60550e736.patch";
+      hash = "sha256-vWqTM6IHL/gBncLk6gZHw+dFe0sdVuPdUqYeVJUbTis=";
+    })
   ];
 
   doCheck = true;