feat: add player hearbeat processing

[lusu007]

Pull Request

Description

Type of Change

• 🐛 Bug fix
• ✨ New feature
• 💥 Breaking change
• ♻️ Refactoring
• 📚 Documentation
• 🔧 Chore

Related Issues

None

Testing

• Unit tests pass
• Manual testing completed
• New tests added for new functionality

Checklist

• I have performed a self-review of my own code
• Tests have been added/updated and pass (if needed)
• Documentation has been updated (if needed)

[Copilot]

Pull request overview

This PR adds player heartbeat processing functionality to track active player sessions. However, there is a typo in the PR title: "hearbeat" should be "heartbeat".

Changes:

• Added last_seen_at timestamp tracking to player sessions with database migration and index
• Implemented batch heartbeat endpoint to update session activity timestamps
• Added scheduled cleanup job to remove stale sessions based on configurable TTL
• Enhanced login flow to handle stale session detection and removal

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
src/main/resources/db/migration/V1__create_player_sessions.sql	Added last_seen_at column with default value and index for efficient stale session queries
src/main/kotlin/gg/grounds/domain/PlayerSession.kt	Extended domain model to include lastSeenAt timestamp
src/main/kotlin/gg/grounds/persistence/PlayerSessionRepository.kt	Added touchSessions for batch updates and deleteStaleSessions for cleanup; updated existing queries
src/main/kotlin/gg/grounds/api/PlayerPresenceGrpcService.kt	Implemented heartbeat batch handler; enhanced login to detect and remove stale sessions
src/main/kotlin/gg/grounds/presence/PlayerSessionCleanup.kt	New scheduled task to automatically clean up stale sessions at configured intervals
src/main/resources/application.properties	Added session TTL and cleanup interval configuration; set global log level to DEBUG
src/test/resources/application.properties	Disabled scheduler in tests to prevent interference
src/test/kotlin/gg/grounds/api/PlayerPresenceGrpcServiceTest.kt	Added comprehensive tests for heartbeat batch and stale session handling
build.gradle.kts	Added scheduler dependency; updated to SNAPSHOT version of gRPC contracts library

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[Copilot]

Pull request overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated 4 comments.

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[lusu007]

Please merge groundsgg/library-grpc-contracts#33 first.
This change depends on the updated gRPC contract release; once the contracts are released, the referenced proto version must be bumped accordingly.