ci: build dated development jars and tagged draft releases

[ryanbarlow97]

Pull requests into main run Java unit tests and publish the runtime JAR with a UTC DEV-YYYYMMDD-HHmm version in its filename and plugin descriptor. Matching numeric v* tags run verification and create a draft release with the runtime JAR, SHA256SUMS, and build.json.

Builds use Ubuntu 24.04, Java 25, and Node.js 24 actions. Private build inputs are pinned by ServerAssets commit and SHA-256; DEPS_TOKEN supplies read access. TLibs is installed through the shared checksum-verifying Maven installer.

Validation:

• Hosted build passed. All 37 unit tests passed.
• Downloaded games-DEV-20260922-1551.jar passed ZIP integrity checks and has the matching embedded plugin version.
• Actionlint and diff checks passed.
• 4 Java compiler warnings; no Node.js action or runner migration annotations.
• Tagged draft publication has not been exercised.

Documentation: TF-Minecraft/Docs#5