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+---
+phase: 22
+slug: add-from-catalog-thread-integration
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-06
+---
+
+# Phase 22 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | bun test + Playwright |
+| **Config file** | `bunfig.toml` / `playwright.config.ts` |
+| **Quick run command** | `bun test` |
+| **Full suite command** | `bun test && bun run test:e2e` |
+| **Estimated runtime** | ~15 seconds (unit) + ~60 seconds (e2e) |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `bun test`
+- **After every plan wave:** Run `bun test && bun run test:e2e`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 15 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 22-01-01 | 01 | 1 | CATFLOW-03 | unit | `bun test tests/services/item.service.test.ts` | TBD | ⬜ pending |
+| 22-01-02 | 01 | 1 | CATFLOW-05 | unit | `bun test tests/services/thread.service.test.ts` | TBD | ⬜ pending |
+| 22-01-03 | 01 | 1 | CATFLOW-06 | unit | `bun test tests/services/thread.service.test.ts` | TBD | ⬜ pending |
+| 22-02-01 | 02 | 2 | CATFLOW-03 | e2e | `bun run test:e2e` | TBD | ⬜ pending |
+| 22-02-02 | 02 | 2 | CATFLOW-05 | e2e | `bun run test:e2e` | TBD | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+*Existing infrastructure covers all phase requirements. Backend already supports globalItemId on items and candidates. No new test framework needed.*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Add-to-collection modal UX flow | CATFLOW-03 | Modal interaction, visual confirmation | Open catalog search, click Add, verify modal shows category picker + notes, submit and verify toast |
+| Thread picker displays active threads | CATFLOW-05 | UI state interaction | Open catalog search in thread mode, click Add, verify thread dropdown shows active threads |
+| Combined thread creation + candidate add | CATFLOW-05 | Multi-step UI flow | From FAB "Start Thread", search, click Add on first item, verify thread creation + candidate in one step |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 15s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending