cleanup: remove clawd/openclaw references, fix permissions, add architecture docs

- Replace all ~/clawd and ~/.clawdbot paths with ~/echo-core equivalents
  in tools (git_commit, ralph_prd_generator, backup_config, lead-gen)
- Update personality files: TOOLS.md repo/paths, AGENTS.md security audit cmd
- Migrate HANDOFF.md architectural decisions to docs/architecture.md
- Tighten credentials/ dir to 700, add to .gitignore
- Add .claude/ and *.pid to .gitignore
- Various adapter, router, and session improvements from prior work

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli.py

@@ -255,9 +255,7 @@ def cmd_restart(args):
         _systemctl("start", BRIDGE_SERVICE_NAME)
 
     print("Restarting Echo Core...")
-    _systemctl("kill", SERVICE_NAME)
-    time.sleep(2)
-    _systemctl("start", SERVICE_NAME)
+    _systemctl("restart", SERVICE_NAME)
     time.sleep(3)
 
     info = _get_service_status(SERVICE_NAME)