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/task-status-reason/BUG_REPORT.md

@@ -0,0 +1,30 @@
+# Bug Report: task-status-reason
+
+## Summary
+Audit of status_reason implementation against SPEC.md found minor issues: a dead-code branch in the status_reason message, and a pre-existing REFEREE state that's never produced.
+
+## Bugs Found
+
+### Bug 1: Dead message branch in status_reason for BLOCKED state
+- **Severity**: Low
+- **Location**: `automaton/dashboard/core/task.py:149`
+- **Description**: The message `"Verdict is empty or could not be parsed"` has two scenarios:
+  1. Empty verdict → reachable (content is `""`, correctly returns this message)
+  2. Unparseable verdict → unreachable. When `parse_verdict_status()` returns `None`, the state machine in `determine_task_state()` doesn't classify the task as BLOCKED — it falls through to earlier state checks. So a task is never both BLOCKED and "could not be parsed".
+- **Suggested Fix**: Change message to `"Verdict is empty"` to accurately reflect the only reachable case.
+
+### Bug 2: REFEREE state never produced by state machine
+- **Severity**: Low
+- **Location**: `automaton/dashboard/core/task.py:174` (fallback `status_reason` line), and `task.py:226-272` (determine_task_state)
+- **Description**: `TaskState.REFEREE` exists in the enum and in the sort order, but `determine_task_state` never returns it. When a VERDICT.md is present but unparseable, the state machine falls through to earlier artifact checks instead of assigning REFEREE. This means the fallback status reason `"In referee phase"` is unreachable, and tasks with ambiguous verdicts silently show as earlier states (e.g., RESEARCH if only SPEC.md exists alongside an unparseable VERDICT.md).
+- **Pre-existing**: This predates the task and is not introduced by the implementation, but the status_reason property exposes it because the REFEREE branch is dead code.
+- **Suggested Fix**: Add `if "VERDICT.md" in artifacts: return TaskState.REFEREE, artifacts` after the terminal-state checks in `determine_task_state()`, before the state machine fallthrough.
+
+### Bug 3: REFEREE status reason is generic
+- **Severity**: Low
+- **Location**: `automaton/dashboard/core/task.py:175`
+- **Description**: The fallthrough line `return f"In {self.state.value} phase"` would produce generic messages like `"In blocked phase"` or `"In done phase"` for states that are handled above it. This is actually dead code for all defined states since every `TaskState` value is covered by an explicit `if` branch. If a new state is added without adding a status_reason handler, it gets a generic message rather than failing loudly.
+- **Suggested Fix**: Replace the fallthrough with a clear signal: either raise an error, or explicitly list the catch to alert developers when adding states.
+
+## Score
++5