Item Despawn Timer — Fabric 26.2 port

This branch is Fabric-only and intentionally separates authority:

• config/item-despawn-timer-server.json — server gameplay: default despawn time and per-item overrides. -1 means infinite when enabled.
• config/item-despawn-timer-client.json — client presentation only: timer/name visibility, heights, threshold and colors.

Minecraft 26.2 uses the unobfuscated Mojang/official names and Java 25. This port therefore does not reuse the old Yarn-named common/client GUI classes from 0.2.2. Client rendering lives only in src/client, while server/gameplay code lives in src/main.

Run compiler.bat on Windows or ./compiler.sh on Linux/macOS. The script checks whether the existing JAR contains the same mod_version+mc<minecraft_version> as gradle.properties; matching builds offer Push/Recompile/Quit. After a successful build it offers Git push and retries failed pushes in groups of three.