Adds WorldEntitySnapshot, IGameState, IEvents abstractions; WorldEvents
implements replay-on-subscribe with per-handler exception swallowing;
WorldGameState tracks entities; AppPluginHost exposes all three; stubs
wired in Program.cs to keep build green ahead of Task 9 live wiring.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Addresses code quality review of ed1c2d0:
- ILogger would collide with Microsoft.Extensions.Logging.ILogger and Serilog.ILogger
in any plugin file that imports both namespaces; renamed to IPluginLogger
- IAcDreamPlugin.Initialize now has an XML doc clarifying its lifecycle contract
