fix: backfill symbol_demand for sidebar-added symbols + analyst ratings schema fix

- Add await ctx.cache.subscribe() to addSymbol mutation so symbols
  added via the sidebar get registered in symbol_demand and yfinance
  jobs are queued immediately
- Backfill PEP, WYNN, STZ, CELH into symbol_demand + adapter_queue
- Upgrade yahoo-finance2 3.15.3 -> 3.15.4 and pass validateResult:false
  to quoteSummary() to handle Yahoo schema drift
- Add error detail logging for analyst ratings schema failures
- Update .gitignore with common ignores

.automaton/TASK_ASSIGNMENT.md

@@ -0,0 +1,44 @@
+# Task Pool — Investor Flow
+
+## Model
+Tasks are NOT pre-assigned. All 21 tasks are in a shared **implement** phase pool.
+Any agent picks the next task they want to work on.
+
+## Pool State
+
+| Status | Count |
+|--------|-------|
+| In implement pool (unclaimed) | 21 |
+| Claimed and in progress | 0 |
+| In code_review | 0 |
+| Complete | 20 |
+
+## How Agents Pick Work
+
+```bash
+# 1. See what's available
+cd /Users/laptran/Documents/investor-flow
+python3 ~/.automaton/scripts/status.py --available --agent <your-name> --project .
+
+# 2. Claim the next task
+python3 ~/.automaton/scripts/status.py --claim --task <task-name> --agent <your-name> --project .
+
+# 3. Implement (read SPEC.md, write code, pass tests)
+
+# 4. Transition to code_review
+python3 ~/.automaton/scripts/status.py --transition code_review --task <task-name> --project .
+
+# 5. Different agent reviews, then completes
+python3 ~/.automaton/scripts/status.py --claim --task <task-name> --agent <reviewer> --project .
+python3 ~/.automaton/scripts/status.py --transition complete --task <task-name> --project .
+```
+
+## Conflict of Interest
+An agent CANNOT review their own implementation. The framework enforces this.
+
+## What's Already Done
+- RiskEngine ADR-0007 footer fix ✓
+- AlertEngine pure core (17 tests) ✓
+- alert_events schema + tRPC endpoints (list, acknowledge) ✓
+- SPEC.md for all 21 tasks ✓
+- 338 tests pass, 0 fail ✓