fix: WASM double-X3DH bug, federated aliases, deploy tooling

WASM fix (critical):
- encrypt_key_exchange_with_id was calling x3dh::initiate a second time,
  generating a new ephemeral key that didn't match the ratchet — receiver
  always failed to decrypt. Now stores X3DH result from initiate() and
  reuses it. Added 2 protocol tests confirming the fix + the bug.
- Bumped service worker cache to wz-v2 to force browsers to re-fetch.
- Disabled wasm-opt for Hetzner builds (libc compat issue).

Federation — alias support:
- resolve_alias falls back to federation peer if not found locally
- register_alias checks peer server before allowing — globally unique aliases
- Added resolve_remote_alias() and is_alias_taken_remote() to FederationHandle

Federation — key proxy fix:
- Remote bundles no longer cached locally (stale cache caused decrypt failures)
- Local vs remote determined by device: prefix in keys DB

Client fixes:
- Self-messaging blocked ("Cannot send messages to yourself")
- /peer <self> blocked
- last_dm_peer never set to self
- /r <message> sends reply inline (switches peer + sends in one command)

Deploy tooling:
- scripts/build-linux.sh with --ship (build + deploy + destroy)
- --update-all, --status, --logs commands
- WASM rebuilt on Hetzner VM before server binary
- deploy/ directory: systemd service, federation configs, setup script
- Journald log cap (50MB, 7-day retention)

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

warzone/deploy/federation-kh3rad3ree.json

@@ -0,0 +1,8 @@
+{
+  "server_id": "kh3rad3ree",
+  "shared_secret": "7cfe41395062d939a36d9debe7d70f528ccd2efaccddca139c19603fe40df8f4",
+  "peer": {
+    "id": "mequ",
+    "url": "http://10.66.66.129:7700"
+  }
+}