docs: document Claude test commands

TASKS.md

@@ -72,3 +72,25 @@ Acceptance Criteria:
 - command reads discovery-log.md
 - low-confidence answers are detected
 - follow-up answers are appended to discovery-log.md
+
+## TASK-005 — Task lifecycle commands
+
+Status: Todo
+
+Goal:
+Allow tasks to be managed from the CLI rather than manually editing TASKS.md.
+
+Acceptance Criteria:
+
+- `rdb start TASK-ID`
+  - Marks task In Progress
+
+- `rdb complete TASK-ID`
+  - Marks task Done
+
+- Updates PROJECT_STATE.md
+- Updates AGENT_HANDOFF.md
+- Updates RUN_LOG.md
+- Preserves task formatting
+- Add/update tests
+- Run python -m pytest