Archive completed tasks, add cleanup commands, self-documenting dashboard UI

- Archive 79 completed framework-dev tasks from tasks/ -> tasks/complete/
- status.py: add --cleanup-done and --install-cleanup-schedule commands
- Add scripts/automaton-cleanup.sh for periodic task archiving
- Dashboard: rename 'Background' tab -> 'Agent', 'Cleanup' agent -> 'Completed Task Archiver', remove redundant group headers and pill badges, dim inactive agent placeholders
- .rules.md: add Self-Documenting UI Names rule
- New tests: test_cleanup_done.py, expanded test_app.py and test_task.py

tasks/complete/fix-cat3-audit-paths/IMPLEMENTATION.md

@@ -0,0 +1,7 @@
+# Implementation: fix-cat3-audit-paths
+
+## Changes
+- **scripts/status.py** `_audit_category3()` (~line 696): Added a second path check for regular projects. Files matching `.automaton/tasks/{task_name}/...` are now correctly recognized as inside task folders, in addition to the existing `tasks/{task_name}/...` check for framework mode.
+
+## Test
+- `tests/test_status.py::TestCat3AuditRegularProjectPaths::test_regular_project_task_path_not_flagged` — verifies that changes inside `.automaton/tasks/` in a regular project are not flagged as unauthorized.