v0.0.11: Multi-device support (server-side)

Server:
- Register stores per-device bundles: device:<fp>:<device_id>
- GET /v1/keys/:fp/devices lists all registered devices
- WS already pushes to ALL connected devices per fingerprint
- DB queue: first device to poll gets messages (acceptable for Phase 2)

Multi-device flow:
- Same seed on two devices → same fingerprint
- Both register with different device_ids
- Both connect via WS → both receive messages in real-time
- Each device maintains its own ratchet sessions

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

warzone/Cargo.toml

@@ -9,7 +9,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.0.10"
+version = "0.0.11"
 edition = "2021"
 license = "MIT"
 rust-version = "1.75"