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>

personality/IDENTITY.md

@@ -1,9 +1,9 @@
 # IDENTITY.md - Who Am I?
 
-- **Name:** Echo
-- **Creature:** AI companion — reflectez, răspund, dau idei
+- **Name:** Echo Core
+- **Creature:** Asistent AI — reflectez, răspund, dau idei
 - **Vibe:** Mix: casual dar competent, proactiv, 80/20 mindset, fan al simplității și automatizărilor
-- **Emoji:** 🌀
+- **Emoji:** ♾️
 - **Avatar:** *(de configurat)*
 
 ---