Implement default available slots provider for surf servers

[twisti-dev]

This pull request introduces a new abstraction for determining available slots on a server and integrates it into the Paper implementation. The main goal is to decouple slot calculation logic from direct Bukkit API usage, making the codebase more modular and extensible.

New abstraction for available slots:

• Added the SurfQueueAvailableSlotsProvider interface to the API, providing a global mechanism to determine available slots for a given SurfServer.
• Implemented the DefaultSurfQueueAvailableSlotsProvider object for the Paper platform, using Bukkit APIs for the current server and fallback logic for others.

Integration and refactoring:

• Registered DefaultSurfQueueAvailableSlotsProvider as the global provider during Paper plugin loading in PaperSurfQueueInstance.
• Refactored PaperQueueTransfer to use the new provider for slot calculation instead of directly accessing Bukkit APIs, improving modularity and testability.

Project versioning:

• Bumped the project version from 1.1.3 to 1.2.0 in gradle.properties.

[Copilot]

Pull request overview

This PR introduces a new API abstraction (SurfQueueAvailableSlotsProvider) to compute available player slots for a SurfServer, and wires a Paper default implementation into the Paper plugin so transfer logic no longer directly depends on Bukkit for slot calculation.

Changes:

• Added SurfQueueAvailableSlotsProvider to surf-queue-api as a global, platform-configurable slot resolution mechanism.
• Implemented and registered DefaultSurfQueueAvailableSlotsProvider in the Paper module.
• Refactored PaperQueueTransfer to use the provider instead of directly querying Bukkit.
• Bumped project version to 1.2.0.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
surf-queue-paper/src/main/kotlin/dev/slne/surf/queue/paper/queue/transfer/PaperQueueTransfer.kt	Uses the new global slots provider for transfer sizing (but currently leaves an unused Bukkit import).
surf-queue-paper/src/main/kotlin/dev/slne/surf/queue/paper/queue/DefaultSurfQueueAvailableSlotsProvider.kt	Adds the Paper default provider for available slots (currently uses Bukkit from a worker thread and can return negative slots).
surf-queue-paper/src/main/kotlin/dev/slne/surf/queue/paper/PaperSurfQueueInstance.kt	Registers the Paper default provider during plugin load.
surf-queue-api/src/main/kotlin/dev/slne/surf/queue/api/SurfQueueAvailableSlotsProvider.kt	Introduces the new provider interface and global accessor.
gradle.properties	Version bump 1.1.3 → 1.2.0.

Comments suppressed due to low confidence (1)

surf-queue-paper/src/main/kotlin/dev/slne/surf/queue/paper/queue/transfer/PaperQueueTransfer.kt:14

• org.bukkit.Bukkit is imported but no longer used in this file after switching slot calculation to SurfQueueAvailableSlotsProvider. Kotlin treats unused imports as compilation errors, so this will fail the build.

import dev.slne.surf.queue.api.SurfQueueAvailableSlotsProvider
import kotlinx.coroutines.TimeoutCancellationException
import kotlinx.coroutines.withTimeout
import net.kyori.adventure.text.Component
import org.bukkit.Bukkit