diff --git a/.planning/10-CONTEXT.md b/.planning/10-CONTEXT.md
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+---
+phase: 10
+title: Branding Data Foundation
+status: ready-for-planning
+created: 2026-04-08
+---
+
+# Phase 10 Context: Branding Data Foundation
+
+## Decided Areas (from prior research + STATE.md)
+
+These are locked — do not re-litigate during planning or execution.
+
+| Decision | Value |
+|---|---|
+| Logo storage format | Base64 strings in JSON (not file paths) |
+| MSP logo location | `BrandingSettings.cs` model → `branding.json` |
+| Client logo location | On `TenantProfile` model (per-tenant) |
+| File path after import | Discarded — only base64 persists |
+| SVG support | Rejected (XSS risk) — PNG/JPG only |
+| User directory service | New `GraphUserDirectoryService`, separate from `GraphUserSearchService` |
+| Directory auto-load | No — explicit "Load Directory" button required |
+| New NuGet packages | None — existing stack covers everything |
+| Export service signature | Optional `ReportBranding? branding = null` parameter on existing export methods |
+
+## Discussed Areas
+
+### 1. Logo Metadata Model
+
+**Decision:** Store base64 + MIME type as separate fields in a shared `LogoData` record.
+
+- Shared model: `LogoData { string Base64, string MimeType }` — used by both MSP logo (in `BrandingSettings`) and client logo (on `TenantProfile`)
+- `MimeType` is `"image/png"` or `"image/jpeg"`, determined at import time from magic bytes
+- No other metadata stored — no original filename, dimensions, or import date
+- Export services concatenate `data:{MimeType};base64,{Base64}` for HTML `<img>` tags
+- WPF preview converts `Base64` bytes to `BitmapImage` directly
+
+### 2. Logo Validation & Compression
+
+**Decision:** Validate format via magic bytes, auto-compress oversized files silently.
+
+- **Format detection:** Read file header magic bytes only — ignore file extension entirely
+  - PNG signature: `89 50 4E 47` (first 4 bytes)
+  - JPEG signature: `FF D8 FF` (first 3 bytes)
+  - Anything else → reject with specific error message (e.g., "File format is BMP, only PNG and JPG are accepted")
+- **Size handling:** If file exceeds 512 KB, auto-compress silently (no user notification)
+  - Strategy: resize dimensions (e.g., max 300px width/height) + reduce quality
+  - Keep original format — PNG stays PNG, JPEG stays JPEG (no format conversion)
+  - Compress until under 512 KB
+- **Dimension limits:** None — the 512 KB cap and compression handle naturally
+- **Validation errors:** Specific messages for format rejection (format-related only, since size is auto-handled)
+
+### 3. Profile Deletion & Duplication Behavior
+
+**Decision:** Warn about logo loss on deletion; do NOT copy logo on duplication.
+
+- **Deletion:** When deleting a tenant profile that has a client logo, the confirmation message explicitly mentions it: "This will also remove its client logo." The logo is embedded in the profile JSON, so deletion is automatic — no orphaned files.
+- **Duplication:** Duplicating a tenant profile copies connection fields (Name, TenantUrl, ClientId) but starts with a blank client logo. The user must re-import or auto-pull for the new profile. Rationale: duplicated profiles are typically for different tenants, so the logo shouldn't carry over.
+
+## Deferred Ideas (out of scope for Phase 10)
+
+- Logo preview in Settings UI (Phase 12)
+- Auto-pull client logo from Entra branding API (Phase 11/12)
+- Report header layout with logos side-by-side (Phase 11)
+- "Load Directory" button placement decision (Phase 14)
+- Session-scoped directory cache (UDIR-F01, deferred)
+
+## code_context
+
+| Asset | Path | Reuse |
+|---|---|---|
+| TenantProfile model | `SharepointToolbox/Core/Models/TenantProfile.cs` | Extend with `LogoData? ClientLogo` property |
+| AppSettings model | `SharepointToolbox/Core/Models/AppSettings.cs` | Reference for BrandingSettings pattern |
+| SettingsRepository | `SharepointToolbox/Infrastructure/Persistence/SettingsRepository.cs` | Clone pattern for BrandingRepository (write-then-replace + SemaphoreSlim) |
+| ProfileRepository | `SharepointToolbox/Infrastructure/Persistence/ProfileRepository.cs` | Already handles TenantProfile persistence — will serialize new logo field |
+| GraphUserSearchService | `SharepointToolbox/Services/GraphUserSearchService.cs` | Reference for Graph SDK usage, auth, and query patterns |
+| GraphClientFactory | `SharepointToolbox/Infrastructure/Auth/GraphClientFactory.cs` | Provides `GraphServiceClient` for new directory service |
+| DI registration | `SharepointToolbox/App.xaml.cs` (lines 73-163) | Register new BrandingRepository, BrandingService, GraphUserDirectoryService |
+| Profile deletion UI | `SharepointToolbox/ViewModels/ProfileManagementViewModel.cs` | Update deletion confirmation message to mention logo |
diff --git a/.planning/phases/10-branding-data-foundation/10-CONTEXT.md b/.planning/phases/10-branding-data-foundation/10-CONTEXT.md
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+---
+phase: 10
+title: Branding Data Foundation
+status: ready-for-planning
+created: 2026-04-08
+---
+
+# Phase 10 Context: Branding Data Foundation
+
+## Decided Areas (from prior research + STATE.md)
+
+These are locked — do not re-litigate during planning or execution.
+
+| Decision | Value |
+|---|---|
+| Logo storage format | Base64 strings in JSON (not file paths) |
+| MSP logo location | `BrandingSettings.cs` model → `branding.json` |
+| Client logo location | On `TenantProfile` model (per-tenant) |
+| File path after import | Discarded — only base64 persists |
+| SVG support | Rejected (XSS risk) — PNG/JPG only |
+| User directory service | New `GraphUserDirectoryService`, separate from `GraphUserSearchService` |
+| Directory auto-load | No — explicit "Load Directory" button required |
+| New NuGet packages | None — existing stack covers everything |
+| Export service signature | Optional `ReportBranding? branding = null` parameter on existing export methods |
+
+## Discussed Areas
+
+### 1. Logo Metadata Model
+
+**Decision:** Store base64 + MIME type as separate fields in a shared `LogoData` record.
+
+- Shared model: `LogoData { string Base64, string MimeType }` — used by both MSP logo (in `BrandingSettings`) and client logo (on `TenantProfile`)
+- `MimeType` is `"image/png"` or `"image/jpeg"`, determined at import time from magic bytes
+- No other metadata stored — no original filename, dimensions, or import date
+- Export services concatenate `data:{MimeType};base64,{Base64}` for HTML `<img>` tags
+- WPF preview converts `Base64` bytes to `BitmapImage` directly
+
+### 2. Logo Validation & Compression
+
+**Decision:** Validate format via magic bytes, auto-compress oversized files silently.
+
+- **Format detection:** Read file header magic bytes only — ignore file extension entirely
+  - PNG signature: `89 50 4E 47` (first 4 bytes)
+  - JPEG signature: `FF D8 FF` (first 3 bytes)
+  - Anything else → reject with specific error message (e.g., "File format is BMP, only PNG and JPG are accepted")
+- **Size handling:** If file exceeds 512 KB, auto-compress silently (no user notification)
+  - Strategy: resize dimensions (e.g., max 300px width/height) + reduce quality
+  - Keep original format — PNG stays PNG, JPEG stays JPEG (no format conversion)
+  - Compress until under 512 KB
+- **Dimension limits:** None — the 512 KB cap and compression handle naturally
+- **Validation errors:** Specific messages for format rejection (format-related only, since size is auto-handled)
+
+### 3. Profile Deletion & Duplication Behavior
+
+**Decision:** Warn about logo loss on deletion; do NOT copy logo on duplication.
+
+- **Deletion:** When deleting a tenant profile that has a client logo, the confirmation message explicitly mentions it: "This will also remove its client logo." The logo is embedded in the profile JSON, so deletion is automatic — no orphaned files.
+- **Duplication:** Duplicating a tenant profile copies connection fields (Name, TenantUrl, ClientId) but starts with a blank client logo. The user must re-import or auto-pull for the new profile. Rationale: duplicated profiles are typically for different tenants, so the logo shouldn't carry over.
+
+## Deferred Ideas (out of scope for Phase 10)
+
+- Logo preview in Settings UI (Phase 12)
+- Auto-pull client logo from Entra branding API (Phase 11/12)
+- Report header layout with logos side-by-side (Phase 11)
+- "Load Directory" button placement decision (Phase 14)
+- Session-scoped directory cache (UDIR-F01, deferred)
+
+## code_context
+
+| Asset | Path | Reuse |
+|---|---|---|
+| TenantProfile model | `SharepointToolbox/Core/Models/TenantProfile.cs` | Extend with `LogoData? ClientLogo` property |
+| AppSettings model | `SharepointToolbox/Core/Models/AppSettings.cs` | Reference for BrandingSettings pattern |
+| SettingsRepository | `SharepointToolbox/Infrastructure/Persistence/SettingsRepository.cs` | Clone pattern for BrandingRepository (write-then-replace + SemaphoreSlim) |
+| ProfileRepository | `SharepointToolbox/Infrastructure/Persistence/ProfileRepository.cs` | Already handles TenantProfile persistence — will serialize new logo field |
+| GraphUserSearchService | `SharepointToolbox/Services/GraphUserSearchService.cs` | Reference for Graph SDK usage, auth, and query patterns |
+| GraphClientFactory | `SharepointToolbox/Infrastructure/Auth/GraphClientFactory.cs` | Provides `GraphServiceClient` for new directory service |
+| DI registration | `SharepointToolbox/App.xaml.cs` (lines 73-163) | Register new BrandingRepository, BrandingService, GraphUserDirectoryService |
+| Profile deletion UI | `SharepointToolbox/ViewModels/ProfileManagementViewModel.cs` | Update deletion confirmation message to mention logo |
diff --git a/.planning/phases/10-branding-data-foundation/10-VALIDATION.md b/.planning/phases/10-branding-data-foundation/10-VALIDATION.md
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+---
+phase: 10
+slug: branding-data-foundation
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-08
+---
+
+# Phase 10 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | xUnit 2.9.3 + Moq 4.20.72 |
+| **Config file** | `SharepointToolbox.Tests/SharepointToolbox.Tests.csproj` |
+| **Quick run command** | `dotnet test --filter "Category=Unit" --no-build` |
+| **Full suite command** | `dotnet test` |
+| **Estimated runtime** | ~15 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `dotnet test --filter "Category=Unit" --no-build`
+- **After every plan wave:** Run `dotnet test`
+- **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 |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 10-01-01 | 01 | 1 | BRAND-01 | unit | `dotnet test --filter "FullyQualifiedName~BrandingRepositoryTests" --no-build` | ❌ W0 | ⬜ pending |
+| 10-01-02 | 01 | 1 | BRAND-06 | unit | `dotnet test --filter "FullyQualifiedName~BrandingServiceTests" --no-build` | ❌ W0 | ⬜ pending |
+| 10-01-03 | 01 | 1 | BRAND-03 | unit | `dotnet test --filter "FullyQualifiedName~ProfileServiceTests" --no-build` | ✅ extend | ⬜ pending |
+| 10-02-01 | 02 | 1 | UDIR-02 | unit | `dotnet test --filter "FullyQualifiedName~GraphUserDirectoryServiceTests" --no-build` | ❌ W0 | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `SharepointToolbox.Tests/Services/BrandingRepositoryTests.cs` — stubs for BRAND-01 persistence round-trip
+- [ ] `SharepointToolbox.Tests/Services/BrandingServiceTests.cs` — stubs for BRAND-06 magic bytes, compression, rejection
+- [ ] `SharepointToolbox.Tests/Services/GraphUserDirectoryServiceTests.cs` — stubs for UDIR-02 pagination
+- [ ] Extend `SharepointToolbox.Tests/Services/ProfileServiceTests.cs` — add BRAND-03 `ClientLogo` round-trip test
+
+*Existing infrastructure covers test framework setup.*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| MSP logo survives app restart | BRAND-01 | Requires full app lifecycle (start, import, close, reopen) | 1. Run app, import MSP logo 2. Close app 3. Reopen app 4. Verify logo still present in branding.json |
+| Client logo isolated between tenants | BRAND-03 | Requires multi-profile JSON inspection | 1. Import logo for Tenant A 2. Verify Tenant B profile has no logo field 3. Delete Tenant A logo 4. Verify Tenant B unaffected |
+
+---
+
+## 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