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+---
+phase: 07
+slug: mode-switcher-week-mode
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-09
+---
+
+# Phase 07 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | vitest 3.x |
+| **Config file** | vitest.config.ts |
+| **Quick run command** | `npx vitest run --reporter=verbose` |
+| **Full suite command** | `npx vitest run --reporter=verbose` |
+| **Estimated runtime** | ~5 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `npx vitest run --reporter=verbose`
+- **After every plan wave:** Run `npx vitest run --reporter=verbose`
+- **Before `/gsd-verify-work`:** Full suite must be green
+- **Max feedback latency:** 5 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Threat Ref | Secure Behavior | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|------------|-----------------|-----------|-------------------|-------------|--------|
+| 07-01-01 | 01 | 1 | VIZ-01 | — | N/A | unit | `npx vitest run` | ❌ W0 | ⬜ pending |
+| 07-01-02 | 01 | 1 | VIZ-05 | — | N/A | unit | `npx vitest run` | ❌ W0 | ⬜ pending |
+| 07-02-01 | 02 | 1 | VIZ-02 | — | N/A | unit | `npx vitest run` | ❌ W0 | ⬜ pending |
+| 07-02-02 | 02 | 1 | TEST-01 | — | N/A | unit | `npx vitest run` | ❌ W0 | ⬜ pending |
+
+*Status: ⬜ pending / ✅ green / ❌ red / ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+*Existing infrastructure covers all phase requirements.*
+
+Vitest is already installed and configured. Test files exist in `assets/test/`. No additional setup needed.
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Segmented control renders in card header | VIZ-01 | Visual layout in Kimai dashboard | Start dev Kimai, verify controls appear in widget header |
+| Week-mode cells colored correctly | VIZ-02 | Visual regression check | Switch to week mode, verify 7 colored cells with correct labels |
+| Mode switch preserves filter | SC-4 | Requires running Kimai with project data | Select a project filter, switch modes, verify filter state retained |
+
+---
+
+## 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 < 5s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending