[nexus] docs(22): add validation strategy

.planning/phases/22-agent-streaming/22-VALIDATION.md

@@ -0,0 +1,83 @@
+---
+phase: 22
+slug: agent-streaming
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-01
+---
+
+# Phase 22 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | Vitest 3.0.x |
+| **Config file** | `server/vitest.config.ts`, `ui/vitest.config.ts` |
+| **Quick run command** | `pnpm --filter @paperclipai/server test run && pnpm --filter @paperclipai/ui test run` |
+| **Full suite command** | `pnpm test run` |
+| **Estimated runtime** | ~20 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `pnpm --filter @paperclipai/server test run && pnpm --filter @paperclipai/ui test run`
+- **After every plan wave:** Run `pnpm test run`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 20 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 22-01-01 | 01 | 1 | CHAT-01 | unit (server) | `pnpm --filter @paperclipai/server test run -- chat-stream` | ❌ W0 | ⬜ pending |
+| 22-01-02 | 01 | 1 | CHAT-08 | unit (server) | `pnpm --filter @paperclipai/server test run -- chat-routes` | ✅ extend | ⬜ pending |
+| 22-01-03 | 01 | 1 | CHAT-10 | unit (server) | `pnpm --filter @paperclipai/server test run -- chat-routes` | ✅ extend | ⬜ pending |
+| 22-02-01 | 02 | 1 | CHAT-12 | unit (UI) | `pnpm --filter @paperclipai/ui test run` | ❌ W0 | ⬜ pending |
+| 22-02-02 | 02 | 1 | INPUT-05 | unit (UI) | `pnpm --filter @paperclipai/ui test run` | ❌ W0 | ⬜ pending |
+| 22-02-03 | 02 | 1 | INPUT-06 | unit (UI) | `pnpm --filter @paperclipai/ui test run` | ❌ W0 | ⬜ pending |
+| 22-02-04 | 02 | 1 | AGENT-04 | unit (UI) | `pnpm --filter @paperclipai/ui test run` | ❌ W0 | ⬜ pending |
+| 22-03-01 | 03 | 2 | PERF-03 | unit (UI) | `pnpm --filter @paperclipai/ui test run` | ✅ extend | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `server/src/__tests__/chat-stream-routes.test.ts` — stubs for CHAT-01, CHAT-12 SSE behavior
+- [ ] `ui/src/components/ChatInput.slash-mention.test.tsx` — stubs for INPUT-05, INPUT-06 parsing
+- [ ] `ui/src/components/ChatAgentBadge.test.tsx` — stubs for AGENT-04 rendering
+
+*Existing `chat-routes.test.ts` covers CHAT-08 and CHAT-10 with extensions.*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| First token appears in under 500ms | PERF-02 | Requires real API latency measurement | Send message, observe time-to-first-token with network tab |
+| Agent colors distinguishable across themes | THEME-03 | Visual perception test | Switch themes, verify agent badges are visually distinct |
+| 1000+ messages scroll without jank | PERF-03 | Requires real browser scroll performance | Load conversation with 1000+ messages, scroll rapidly, check for frame drops |
+
+---
+
+## 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 < 20s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending