v0.16.4

Added

• Border Replacer: rounded corners - set a per-style corner radius to match players that clip poster corners. The border band and the template's inner glow continue around the arc. Solid and gradient borders only.
• Docker: a UMASK environment variable so container-created files can be group-writable.

Fixed

• Native install: numpy version constraints adjusted for FreeBSD compatibility, with build notes added to the install guide.