Fix Paper 26 startup issues

[Riqqqque]

Summary

• update Floodgate's Cloud dependencies so command registration works on newer Paper builds
• normalize locale lookups and guard the fallback path so missing locale state does not blow up startup
• eagerly preload the Spigot injector runtime classes so Paper does not try to lazy-load them from a closing plugin jar on Netty threads

Root cause

• the older Cloud versions in Floodgate fail against newer Paper item parsing internals
• locale fallback assumed the default locale properties were always loaded
• the injector still relied on lazy class loading during connection setup

Validation

• .\gradlew.bat clean build

[SleepyPopp]

Thank you for the PR! However, there is already a experimental Floodgate/Floodgate-Modded build available for Java 26.1.

Additionally, if your going to utilize AI to contribute to GeyserMC projects, please see our AI policy: https://github.com/GeyserMC/.github/blob/master/AI_POLICY.md

Experimental Floodgate Builds:

• Floodgate: Update cloud-paper to 2.0.0-SNAPSHOT for Paper 26.1 support #661
• Floodgate-Modded: Initial support for Floodgate-Fabric and Floodgate-NeoForge for Java 26.1 Floodgate-Modded#159

[Novampr]

Similar to what sleepy and I said on the Geyser PR you did, but again, appreciated nonetheless :)