Provide AWS Gamelift PlacementId

[kedigby]

Would like to provide PlacementId, so that gamesession placement request only happens once.

Solution 1

Add RPC to GameLiftFleetManager, which calls GenerateCallbackId.

Our implementation calls RPC prior to Create and passes through in the metadata, if the PlacementId is not in the metadata then the GenerateCallbackId() method is used to create PlacementId

Solution 2

Expose public method GeneratePlacementId, which is called in our implementation prior to Create and passes through in the metadata

Changes

• Expose public method GeneratePlacementId
• Create RPC GetPlacementId

[CLAassistant]

All committers have signed the CLA.

[Copilot]

Pull Request Overview

This PR adds support for providing a PlacementId to AWS GameLift game session placement requests to ensure placement requests only happen once. The implementation provides two approaches: accepting a PlacementId through metadata in the Create method, and exposing methods to generate placement IDs.

Key changes:

• Added PlacementIdKey constant and metadata handling in Create method
• Exposed public GeneratePlacementId method and GetPlacementId RPC endpoint
• Fixed a bug in playerLatencies slice initialization

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}