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>

tools/git_commit.py

@@ -9,7 +9,7 @@ import sys
 import os
 from datetime import datetime
 
-REPO_PATH = os.path.expanduser("~/clawd")
+REPO_PATH = os.path.expanduser("~/echo-core")
 
 def run(cmd, capture=True):
     result = subprocess.run(cmd, shell=True, cwd=REPO_PATH,