Merge branch 'js/fix-open-exec'

This addresses CVE-2025-46835, Git GUI can create and overwrite a
user's files:

When a user clones an untrusted repository and is tricked into editing
a file located in a maliciously named directory in the repository, then
Git GUI can create and overwrite files for which the user has write
permission.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>

diff --cc git-gui/git-gui.sh
Simple merge

diff --cc git-gui/lib/blame.tcl
Simple merge

diff --cc git-gui/lib/branch.tcl
Simple merge

diff --cc git-gui/lib/browser.tcl
Simple merge

diff --cc git-gui/lib/checkout_op.tcl
Simple merge

diff --cc git-gui/lib/choose_repository.tcl
Simple merge

diff --cc git-gui/lib/choose_rev.tcl
Simple merge

diff --cc git-gui/lib/commit.tcl
Simple merge

diff --cc git-gui/lib/console.tcl
Simple merge

diff --cc git-gui/lib/database.tcl
Simple merge

diff --cc git-gui/lib/diff.tcl
Simple merge

diff --cc git-gui/lib/index.tcl
Simple merge

diff --cc git-gui/lib/merge.tcl
Simple merge

diff --cc git-gui/lib/mergetool.tcl
Simple merge

diff --cc git-gui/lib/remote.tcl
Simple merge

diff --cc git-gui/lib/remote_branch_delete.tcl
Simple merge

diff --cc git-gui/lib/shortcut.tcl
Simple merge

diff --cc git-gui/lib/sshkey.tcl
Simple merge

diff --cc git-gui/lib/tools.tcl
Simple merge

diff --cc git-gui/lib/win32.tcl
Simple merge