v0.0.22: version bump, ETH identity in web client, version bump rule

Version:
- Workspace + protocol: 0.0.21 → 0.0.22
- Web client VERSION: 0.0.17 → 0.0.22
- Service worker cache: wz-v2 → wz-v3

ETH identity:
- Added WasmIdentity::eth_address() export (derives from seed via secp256k1)
- Web client sends eth_address during key registration
- Identity display shows ETH address first, then fingerprint
- No more server-side resolve needed — computed client-side

CLAUDE.md:
- Added MANDATORY version bump rule (4 places to update)
- Must bump on every functional change, never skip SW cache

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

warzone/crates/warzone-protocol/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "warzone-protocol"
-version = "0.0.21"
+version = "0.0.22"
 edition = "2021"
 license = "MIT"
 description = "Core crypto & wire protocol for featherChat (Warzone messenger)"