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/fix-status-script-bugs/SPEC.md

@@ -1,19 +0,0 @@
-# Fix status.py Bugs
-
-## Problem
-1. **Neutered target-phase artifact check** (status.py:488-492): loop body is `pass`, check never executes
-2. **Double `continue`** (status.py:1003-1004, 1057-1058): unreachable dead code
-3. **`cmd_approve` uses `_read_state`** (status.py:521): weaker than `_require_state`, silently handles untracked tasks
-4. **No `--list-states` command**: agents can't discover valid phases programmatically
-
-## Fix
-1. Activate target-phase artifact check (remove `pass`, add actual validation)
-2. Remove duplicate `continue` statements
-3. Change `cmd_approve` to use `_require_state` for consistency
-4. Add `--list-states` argument that prints VALID_PHASES
-
-## Verification
-- Target-phase artifact check blocks transitions when target's required artifact is missing
-- No dead code
-- `cmd_approve` rejects untracked tasks
-- `--list-states` prints all valid phases