Log Message:
net/syncthing: Update syncthing to 1.26.1

Tested on netbsd-10 amd64 against Android syncthing from F-Droid, and
previous pkgsrc syncthing on older macOS.

Update prepared in wip by Kevin Bloom.

Updates from 1.26.0 -> 1.26.1:
- Fixed display error with login screen

Updates from 1.25.0 -> 1.26.0:
- Omitting %s from LDAP search filter results in corrupt search filter
- Posting config with invalid versioner type causes panic
- Deduplicated files on Windows aren't treated as regular files any more (Go 1.21)
- Syncthing Docker container fails to start if underlying filesystem doesn't \ 
support chown
-  traefik no longer url escape X-Forwarded-Tls-Client-Cert header
- Favicon is stuck in notify state
- Use a real login screen + sessions instead of HTTP basic auth

Updates from 1.24.0 -> 1.25.0:
- v1.23.6 introduced untrusted sharing regression
- Record more performance metrics
- Announce IPv6 ULA
- Restore versions file filter should be case insensitive
- Check interface for FlagRunning
- ClusterConfig called on closed or nonexistent connection
- Build with Go 1.21 out of the box