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/inflight-upgrade-path/ADVERSARIAL_BUG_REPORT.md

@@ -1,13 +0,0 @@
-# Adversarial Bug Report: Inflight Upgrade Path
-
-## Deep Review
-The upgrade path is designed for backward compatibility. Existing tasks without `.state` get bootstrapped via the artifact heuristic. The version marker in config.md enables future version detection.
-
-## Potential Issues
-1. **Bootstrap phase inference may be wrong**: The artifact heuristic determines phase based on which artifacts exist, but this can be ambiguous. For example, if a task has both SPEC.md and IMPLEMENTATION.md (because it was in early implement phase), the heuristic must infer "implement" correctly. The heuristic uses a priority order (latest phase with all required artifacts), which is reasonable but could misidentify tasks that were abandoned mid-phase.
-
-2. **upgrade.sh has no rollback**: If the upgrade script bootstraps a `.state` with an incorrect inferred phase, there's no automatic rollback. The user must manually correct the `.state` file. The script reports inferred phases for review, but doesn't provide a `--dry-run` flag.
-
-3. **Version marker parsing**: `config.md` is a markdown file, so parsing the version marker requires string matching rather than structured format. If someone reformats config.md, the version detection could fail.
-
-## Verdict: PASS — the bootstrap heuristic is reasonable and upgrade.sh reports results for manual review. No critical bugs.