syncthing: bump to 2.0.9

syncthing: bump to 2.0.9

Major version change that switches DB backend from
LevelDB to SQLite. Requires golang 1.24+.

- improve syncthing argument parsing to be more
  robust
- remove unused and add updated config options

Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.0
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.1
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.2
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.3
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.4
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.5
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.6
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.7
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.8
Changelog: https://github.com/syncthing/syncthing/releases/tag/v2.0.9
Signed-off-by: George Sapkin <[email protected]>
wip

Signed-off-by: George Sapkin <[email protected]>