Add 5.x beta preview: What's New, Access Control (RBAC), ProxyBridge, WhisperControl Document everything added since the last stable release (4.1.0): - What's New — 5.x Beta: overview + version history of the whole 5.x line - Access Control (RBAC): roles/groups/tokens, HTTP API, perms command reference - ProxyBridge: the companion Fabric mod (waypoints, pearl-pull-anywhere, /pb admin, position reporting, off-chat /pb goto) - WhisperControl: whisper verbs — protect (new 5.3), come, goto (new 5.3), patrol, mine - Wire all four into the sidebar, Home, and Command Reference (beta-flagged)