v0.0.36: web call UI — call/accept/reject/hangup with signaling

Web client:
- Call bar between header and messages (hidden when idle)
- Call button appears when peer is set (not group)
- Incoming call: pulsing notification + Accept/Reject buttons
- Call states: idle → calling → ringing → active
- /call, /accept, /reject, /hangup slash commands
- CallSignal sent via WS binary frames (same as messages)
- handleCallSignal processes Offer/Answer/Hangup/Reject/Ringing/Busy
- Vibration on incoming call (mobile)
- create_call_signal WASM import wired up

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

warzone/Cargo.lock

@@ -2956,7 +2956,7 @@ dependencies = [
 
 [[package]]
 name = "warzone-client"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "anyhow",
  "argon2",
@@ -2989,7 +2989,7 @@ dependencies = [
 
 [[package]]
 name = "warzone-mule"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "anyhow",
  "clap",
@@ -2998,7 +2998,7 @@ dependencies = [
 
 [[package]]
 name = "warzone-protocol"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "base64",
  "bincode",
@@ -3023,7 +3023,7 @@ dependencies = [
 
 [[package]]
 name = "warzone-server"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "anyhow",
  "axum",
@@ -3053,7 +3053,7 @@ dependencies = [
 
 [[package]]
 name = "warzone-wasm"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "base64",
  "bincode",