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

.rules.md

@@ -50,3 +50,17 @@
 - Write task artifacts atomically to avoid partial reads by the dashboard or other agents
 - Prefer writing to a temporary file and renaming it into place
 - Avoid leaving empty or malformed artifacts in the task folder
+
+## Self-Documenting UI Names
+- All user-facing labels must be self-documenting and free of internal jargon
+- A user should understand what something is without knowing the codebase internals
+- Terms like "tick", "loop", "state", or "phase transition" are internal terminology — never use them directly in UI elements
+- Pick names that describe what something *does*, not what it's called in code
+- Past failure (1): "Loop Tick" in the Background tab — user asked "What is loop tick?" because it's scheduler jargon
+- Past failure (2): "Loop" — still too vague, user said "I don't know what the loop is"
+- Past failure (3): "Loop Agent" — user asked "How do I differentiate between agents with different roles?" because the name described the mechanism (loop) not the purpose
+- Past failure (4): "Background" tab — the tab name described the *location* (background), not the *content* (agents). Renamed to "Agent" tab.
+- Past failure (5): Group headers + agent type pill badge + icon + name all repeated the same info ("🧹 Cleanup" seen 3 times per card). Removed group headers and pill badges — only icon + name on each card.
+- Past failure (6): "Cleanup" agent was vague — renamed to "Completed Task Archiver" which describes what it actually does.
+- Rule: Every agent type must have a self-documenting name ending with its function (e.g., "Archiver", "Scanner", "Processor"). If multiple instances exist, list each instance card.
+- Agent types with no active instances render as dimmed placeholder cards rather than being hidden, so the user always sees the full roster of available agents.