refactor: restructure workspace file organization (#121) (#122)

## Path Changes
- audit.log: memory/audit.log → log/audit.log
- projects.json: memory/projects.json → projects/projects.json
- prompts: roles/<project>/<role>.md → projects/prompts/<project>/<role>.md

## Files Updated
- lib/audit.ts - new audit log path
- lib/projects.ts - new projects.json path
- lib/dispatch.ts - new prompt instructions path
- lib/tools/project-register.ts - prompt scaffolding path
- lib/setup/workspace.ts - workspace scaffolding paths
- lib/context-guard.ts - projects.json path
- lib/tools/setup.ts - tool description
- lib/templates.ts - AGENTS.md template path references

## Documentation Updated
- README.md
- docs/ARCHITECTURE.md
- docs/ONBOARDING.md
- docs/QA_WORKFLOW.md
- docs/ROADMAP.md
- docs/TESTING.md

Addresses issue #121

docs/QA_WORKFLOW.md

@@ -95,9 +95,8 @@ As of [current date], QA workers are instructed via role templates to:
 - Include specific details about what was tested
 - Document results, environment, and any notes
 
-Role templates affected:
-- `roles/default/qa.md`
-- `roles/devclaw/qa.md`
+Prompt templates affected:
+- `projects/prompts/<project>/qa.md`
 - All project-specific QA templates should follow this pattern
 
 ## Best Practices