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/crates/warzone-server/src/routes/aliases.rs

@@ -152,6 +152,13 @@ async fn register_alias(
         delete_alias_record(&state.db.aliases, &existing)?;
     }
 
+    // Check if alias is taken on federation peer (globally unique)
+    if let Some(ref federation) = state.federation {
+        if federation.is_alias_taken_remote(&alias).await {
+            return Ok(Json(serde_json::json!({ "error": "alias already taken on federated server" })));
+        }
+    }
+
     // Remove old alias for this fingerprint (one alias per person)
     if let Some(old_alias_bytes) = state.db.aliases.get(format!("fp:{}", fp).as_bytes())? {
         let old_alias = String::from_utf8_lossy(&old_alias_bytes).to_string();
@@ -292,7 +299,20 @@ async fn resolve_alias(
                 })))
             }
         }
-        None => Ok(Json(serde_json::json!({ "error": "alias not found" }))),
+        None => {
+            // Try federation peer
+            if let Some(ref federation) = state.federation {
+                if let Some(fp) = federation.resolve_remote_alias(&alias).await {
+                    tracing::info!("Alias @{} resolved via federation: {}", alias, fp);
+                    return Ok(Json(serde_json::json!({
+                        "alias": alias,
+                        "fingerprint": fp,
+                        "federated": true,
+                    })));
+                }
+            }
+            Ok(Json(serde_json::json!({ "error": "alias not found" })))
+        }
     }
 }