cygwin 3.6.7-1

[corinna-cygwin@cygwin.com]

The following packages have been uploaded to the Cygwin distribution:

* cygwin-3.6.7-1
* cygwin-devel-3.6.7-1
* cygwin-doc-3.6.7-1

Fixes:
------

- Guard c32rtomb() against invalid input characters.
  Addresses a testsuite error in current gawk git master.

- Allow changing primary group even when running with cygserver account
  caching.
  Addresses: https://cygwin.com/pipermail/cygwin/2026-January/259250.html

- Correctly handle i->İ, I->ı conversion in turk and azerbaijani languages
  (LC_CTYPE=tr_TR, tr_CY, az_AZ).

- Fix uid/gid mapping from unix id to Cygwin id in certain scenarios when
  accessing Samba or NFS shares on unixoid OS.

- gencat: Fix a bug in octal value handling in catalog input files.
  Addresses a flaw in tcsh's cataloge file generation.

- Bump default_POSIX_C_SOURCE to 202405.