Null Presence 1.6.14 - Forge 1.20.1 port

Changes applied:
- NeoForge metadata changed to Forge javafml metadata.
- pack.mcmeta pack_format changed to 15 for Minecraft 1.20.1.
- Datapack folders renamed back to the 1.20.1 names: functions, advancements, structures, tags/functions.
- 1.21 item component syntax converted to 1.20.1 item NBT for the Null armor stand model item.
- /return early exits were emulated with scoreboard flow flags because 1.20.1 does not support /return.
- /random value calls were replaced with a deterministic gametime-based scoreboard pseudo-random fallback because 1.20.1 does not support /random.

Note: This is a direct compatibility port from the supplied jar, not a full source-level Forge rebuild.

PORT SIZE UPDATE:
- Null visual item_display scale changed to [1.0f,0.9f,1.0f].
- Model is 16x32 units, so final visible size is approximately 1 block wide and 1.8 blocks tall, matching the reference screenshot.
- Null vertical display offset raised by +0.9 blocks so the feet stay on the ground and do not sink into terrain.

- v1.6.15: made Null behavior more unpredictable without changing size. Natural spawns now vary position and audio, lurking spawns can appear in the periphery, echoes can appear from multiple angles, window watchers do not always announce themselves the same way, and fear events can now trigger peripheral echoes, door knocks, underfoot scrapes, and watcher-circle moments.
