0.3.1-phase1
- Changed the new-install HEAD_POSITION vertical offset default from +0.30 m to +0.15 m.
- Added configVersion 4 migration.
- Automatically changes the untouched 0.3.0 HEAD_POSITION height of +0.30 m to +0.15 m once.
- Preserves other customized vertical offsets and the complete working HEAD_POSITION implementation.

0.3.0-phase1
- Added HEAD_POSITION tracking mode.
- Reads Epic Fight's composed animated Head-joint displacement each rendered frame.
- Applies the same player model matrix and renderer orientation used by Epic Fight.
- Keeps Vivecraft/HMD camera rotation unchanged; only camera position is adjusted.
- Adds the animated Head displacement on top of the existing body-relative fixed offsets.
- Automatically falls back to the complete 0.2.0 FIXED behavior when Head tracking is unavailable or fails.
- No movement-distance limit is applied.
- Caches Head-joint lookup, rest position, and repeated eye-pass samples to reduce overhead.
- Migrates existing config files to configVersion 3 and defaults to HEAD_POSITION.
