feat(pack): enable Distant Horizons by default

The server generates and serves DH LODs, but DH was opted out by default,
so clients never received them. Default it on (still optional/opt-out) so
players get server-side distant terrain out of the box.

mods/distanthorizons.pw.toml

@@ -4,7 +4,7 @@ side = "both"
 
 [option]
 optional = true
-default = false
+default = true
 description = "Extended render distance via level-of-detail terrain (heavy on GPU/VRAM)"
 
 [download]