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+---
+phase: 5
+slug: distribution-and-hardening
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-03
+---
+
+# Phase 5 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | xUnit 2.9.3 |
+| **Config file** | SharepointToolbox.Tests/SharepointToolbox.Tests.csproj |
+| **Quick run command** | `dotnet test SharepointToolbox.Tests/SharepointToolbox.Tests.csproj --no-build -v quiet` |
+| **Full suite command** | `dotnet test SharepointToolbox.Tests/SharepointToolbox.Tests.csproj -v quiet` |
+| **Estimated runtime** | ~15 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `dotnet test SharepointToolbox.Tests/SharepointToolbox.Tests.csproj --no-build -v quiet`
+- **After every plan wave:** Run `dotnet test SharepointToolbox.Tests/SharepointToolbox.Tests.csproj -v quiet`
+- **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 |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 05-01-01 | 01 | 0 | SC-2-retry | unit | `dotnet test --filter "ExecuteQueryRetryHelper"` | ❌ W0 | ⬜ pending |
+| 05-01-02 | 01 | 0 | SC-4-paginat | unit | `dotnet test --filter "SharePointPagination"` | ❌ W0 | ⬜ pending |
+| 05-01-03 | 01 | 0 | SC-3-fr | unit | `dotnet test --filter "LocaleCompleteness"` | ❌ W0 | ⬜ pending |
+| 05-02-01 | 02 | 1 | FOUND-11 | smoke | `dotnet publish ... && ls pub/*.dll \| wc -l` (expect 0) | ❌ W0 | ⬜ pending |
+| 05-03-01 | 03 | 1 | SC-2-retry | unit | `dotnet test --filter "ExecuteQueryRetryHelper"` | ❌ W0 | ⬜ pending |
+| 05-04-01 | 04 | 1 | SC-3-fr | unit | `dotnet test --filter "LocaleCompleteness"` | ❌ W0 | ⬜ pending |
+| 05-05-01 | 05 | 2 | FOUND-11-b | manual | N/A — clean VM smoke test | N/A | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `SharepointToolbox.Tests/Services/ExecuteQueryRetryHelperTests.cs` — stubs for SC-2-retry
+- [ ] `SharepointToolbox.Tests/Services/SharePointPaginationHelperTests.cs` — stubs for SC-4-paginat
+- [ ] `SharepointToolbox.Tests/Localization/LocaleCompletenessTests.cs` — stubs for SC-3-fr
+- [ ] `ExecuteQueryRetryHelper.IsThrottleException` changed to `internal static`
+- [ ] `SharePointPaginationHelper.BuildPagedViewXml` changed to `internal static`
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| App launches on clean machine | FOUND-11-b | Requires clean Windows VM with no .NET runtime | 1. Copy EXE to clean VM 2. Double-click 3. Verify app launches and main window renders |
+| No diacritic-missing strings in FR | SC-3-fr | Visual inspection of UI strings | 1. Switch language to French 2. Navigate all tabs 3. Verify no bare ASCII where accents expected |
+| 5,000+ item scan completes | SC-4-paginat | Requires live SharePoint tenant with >5k items | 1. Connect to test tenant 2. Run permissions/storage scan on large library 3. Verify result count matches known dataset |
+
+---
+
+## 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