Fix buffer overread in Win32Handler.getShortPathName causing null characters in command lines (#26)

* Initial plan

* Fix null character in Win32Handler.getShortPathName

The issue was that GetShortPathName returns the total length of the shortened path (including prefix like \\?\), but when creating the String from the buffer with an offset, we need to use (newLength - offset) as the length parameter, not newLength. This was causing the String constructor to read past the actual data, picking up null characters from the uninitialized buffer.

Co-authored-by: laeubi <1331477+laeubi@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: laeubi <1331477+laeubi@users.noreply.github.com>

Author: Copilot

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/Win32Handler.java

@@ -118,7 +118,7 @@ public static String getShortPathName(String longPath) {
 		int newLength = com.sun.jna.platform.win32.Kernel32.INSTANCE.GetShortPathName(longPath, buffer, buffer.length);
 		if (0 < newLength && newLength < buffer.length) { // zero means error
 			int offset = longPath.startsWith(WIN32_UNC_RAW_PATH_PREFIX) ? WIN32_UNC_RAW_PATH_PREFIX.length() : WIN32_RAW_PATH_PREFIX.length();
-			return new String(buffer, offset, newLength);
+			return new String(buffer, offset, newLength - offset);
 		}
 		return null;
 	}