fbt/ufbt: Ensure POSIX paths are passed to GDB on all platforms

https://github.com/flipperdevices/flipperzero-firmware/pull/3360/files

scripts/fbt/util.py

@@ -1,5 +1,9 @@
 import os
 import re
+import subprocess
+import sys
+import webbrowser
+from pathlib import Path, PurePosixPath
 
 import SCons
 from SCons.Errors import StopError
@@ -80,6 +84,27 @@ def resolve_real_dir_node(node):
     raise StopError(f"Can't find absolute path for {node.name} ({node})")
 
 
+class PosixPathWrapper:
+    def __init__(self, pathobj):
+        self.pathobj = pathobj
+
+    @staticmethod
+    def fixup_separators(path):
+        if SCons.Platform.platform_default() == "win32":
+            return path.replace(os.path.sep, os.path.altsep)
+        return path
+
+    @staticmethod
+    def fix_path(path):
+        return str(PurePosixPath(Path(path).as_posix()))
+
+    def __call__(self, target, source, env, for_signature):
+        if for_signature:
+            return self.pathobj
+
+        return self.fix_path(env.subst(self.pathobj))
+
+
 def path_as_posix(path):
     if SCons.Platform.platform_default() == "win32":
         return path.replace(os.path.sep, os.path.altsep)