chore: release 0.9.0 — security hardening + warn-don't-block network policy

Release 0.9.0 covering the merged security/reliability PRs (#106 deps/
supply-chain, #107 auth/network, #108 test stability, #110 tmux cwd) plus:

- Network policy: a non-loopback bind without CODEMAN_PASSWORD now STARTS
  with a loud warning (3 ways to secure) instead of refusing to start.
  Loopback stays the safe default. --allow-unauthenticated-network just
  acknowledges (terser note). (src/web/server.ts start())
- Post-install security note explaining the loopback default + safe exposure.
- New docs/security-architecture.md documenting the full model (binding,
  auth pipeline, tunnel req.ip caveat, file-serving, supply-chain, isolation,
  recommended setups). CLAUDE.md Security section + gotcha updated.
- Updated auth-security test: asserts warn-and-start (not throw).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "aicodeman",
-  "version": "0.8.2",
+  "version": "0.9.0",
   "description": "The missing control plane for AI coding agents - run 20 autonomous agents with real-time monitoring and session persistence",
   "type": "module",
   "main": "dist/index.js",