chore: complete v1.0 milestone

Archive 5 phases (36 plans) to milestones/v1.0-phases/.
Archive roadmap, requirements, and audit to milestones/.
Evolve PROJECT.md with shipped state and validated requirements.
Collapse ROADMAP.md to one-line milestone summary.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.planning/milestones/v1.0-phases/03-storage/03-02-SUMMARY.md

@@ -0,0 +1,94 @@
+---
+phase: 03
+plan: 02
+title: StorageService — CSOM StorageMetrics Scan Engine
+subsystem: storage
+tags: [csom, storage-metrics, scan-engine, c#]
+status: complete
+
+dependency_graph:
+  requires:
+    - 03-01 (StorageNode, StorageScanOptions, IStorageService, export stubs, test scaffolds)
+  provides:
+    - StorageService (IStorageService implementation — CSOM scan engine)
+  affects:
+    - 03-07 (StorageViewModel will consume IStorageService via DI)
+
+tech_stack:
+  added: []
+  patterns:
+    - CSOM StorageMetrics loading pattern (ctx.Load with f => f.StorageMetrics expression)
+    - ExecuteQueryRetryHelper.ExecuteQueryRetryAsync for all CSOM round-trips
+    - Recursive subfolder scan with system folder filtering (Forms/, _-prefixed)
+    - CancellationToken guard at top of every recursive step
+
+key_files:
+  created:
+    - SharepointToolbox/Services/StorageService.cs
+    - SharepointToolbox/Services/Export/StorageCsvExportService.cs
+    - SharepointToolbox/Services/Export/StorageHtmlExportService.cs
+    - SharepointToolbox/Services/Export/SearchCsvExportService.cs
+    - SharepointToolbox/Services/Export/SearchHtmlExportService.cs
+    - SharepointToolbox/Services/Export/DuplicatesHtmlExportService.cs
+    - SharepointToolbox.Tests/Services/StorageServiceTests.cs
+    - SharepointToolbox.Tests/Services/SearchServiceTests.cs
+    - SharepointToolbox.Tests/Services/DuplicatesServiceTests.cs
+    - SharepointToolbox.Tests/Services/Export/StorageCsvExportServiceTests.cs
+    - SharepointToolbox.Tests/Services/Export/StorageHtmlExportServiceTests.cs
+    - SharepointToolbox.Tests/Services/Export/SearchExportServiceTests.cs
+    - SharepointToolbox.Tests/Services/Export/DuplicatesHtmlExportServiceTests.cs
+  modified: []
+
+decisions:
+  - StorageService.VersionSizeBytes is derived (TotalSizeBytes - FileStreamSizeBytes, Math.Max 0) — not stored separately; set on StorageNode model
+  - System folder filter uses Forms/ and _-prefix heuristic — matches SharePoint standard hidden folders
+  - LastModified uses StorageMetrics.LastModified with fallback to Folder.TimeLastModified — StorageMetrics.LastModified may be DateTime.MinValue for empty libraries
+
+metrics:
+  duration: "1 min"
+  completed_date: "2026-04-02"
+  tasks_completed: 1
+  files_created: 13
+  files_modified: 0
+---
+
+# Phase 3 Plan 02: StorageService — CSOM StorageMetrics Scan Engine Summary
+
+**One-liner:** CSOM scan engine implementing IStorageService using Folder.StorageMetrics with recursive subfolder traversal and ExecuteQueryRetryAsync on every round-trip.
+
+## What Was Built
+
+`StorageService` is the concrete implementation of `IStorageService`. It takes an already-authenticated `ClientContext` from the ViewModel and:
+
+1. Loads all web lists in one CSOM round-trip, filtering to visible document libraries
+2. For each library root folder, loads `Folder.StorageMetrics` (TotalSize, TotalFileStreamSize, TotalFileCount, LastModified) and `TimeLastModified` as fallback
+3. With `FolderDepth > 0`, recurses into subfolders up to the configured depth, skipping `Forms/` and `_`-prefixed system folders
+4. Returns a flat `IReadOnlyList<StorageNode>` where library roots are at `IndentLevel=0` and subfolders at `IndentLevel=1+`
+
+## Deviations from Plan
+
+### Auto-fixed Issues
+
+**1. [Rule 3 - Blocking] Phase 3 export stubs and test scaffolds were absent**
+- **Found during:** Pre-task check for 03-01 prerequisites
+- **Issue:** Plan 03-01 models and interfaces existed on disk but the 5 export service stubs and 7 test scaffold files were not yet created, preventing `StorageServiceTests` from being discovered and the test filter commands from working
+- **Fix:** Created all 5 export stubs (`StorageCsvExportService`, `StorageHtmlExportService`, `SearchCsvExportService`, `SearchHtmlExportService`, `DuplicatesHtmlExportService`) and 7 test scaffold files as specified in plan 03-01
+- **Files modified:** 12 new files in `SharepointToolbox/Services/Export/` and `SharepointToolbox.Tests/Services/`
+- **Commit:** 08e4d2e
+
+## Test Results
+
+| Test Class | Passed | Skipped | Failed |
+|---|---|---|---|
+| StorageServiceTests | 2 (VersionSizeBytes) | 2 (CSOM) | 0 |
+| DuplicatesServiceTests | 5 (MakeKey) | 2 (CSOM) | 0 |
+
+Build: 0 errors, 0 warnings.
+
+## Self-Check: PASSED
+
+- FOUND: SharepointToolbox/Services/StorageService.cs
+- FOUND: SharepointToolbox/Services/Export/StorageCsvExportService.cs
+- FOUND: SharepointToolbox.Tests/Services/StorageServiceTests.cs
+- FOUND: commit b5df064 (feat(03-02): implement StorageService...)
+- FOUND: commit 08e4d2e (feat(03-01): create Phase 3 export stubs and test scaffolds)