fix: v0.1.15 — production hardening (7 fixes)

Broker:
- Sweep stale presences (3 missed pings = disconnect, 30s interval)
- Exclude sender from broadcast fan-out + queue drain

CLI:
- Decrypt fallback: try base64 plaintext if crypto_box fails
- Stable session keypair across WS reconnects
- Peer name cache (30s TTL) instead of list_peers per push
- Clean up orphaned tmpdirs from crashed sessions (>1 hour old)
- Read displayName from config file (not just env var)

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

apps/cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "claudemesh-cli",
-  "version": "0.1.14",
+  "version": "0.1.15",
   "description": "Claude Code MCP client for claudemesh — peer mesh messaging between Claude sessions.",
   "keywords": [
     "claude-code",