docs: map existing codebase

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

.planning/codebase/STACK.md

@@ -0,0 +1,103 @@
+# Technology Stack
+
+**Analysis Date:** 2026-04-02
+
+## Languages
+
+**Primary:**
+- PowerShell 5.1+ - All application logic, UI, and SharePoint integration
+
+## Runtime
+
+**Environment:**
+- Windows PowerShell 5.1+ or PowerShell Core 7.0+
+- .NET Framework (built-in with PowerShell)
+
+**Execution Model:**
+- Desktop application (WinForms GUI)
+- Synchronous runspace threading for async operations without blocking UI
+
+## Frameworks
+
+**UI:**
+- System.Windows.Forms (native .NET, bundled with PowerShell)
+- System.Drawing (native .NET for graphics and colors)
+
+**SharePoint/Cloud Integration:**
+- PnP.PowerShell (latest version) - All SharePoint Online API interactions
+- Azure AD App Registration for authentication (required)
+
+**Testing:**
+- No dedicated test framework detected (manual testing assumed)
+
+**Build/Dev:**
+- No build system (single .ps1 script file executed directly)
+
+## Key Dependencies
+
+**Critical:**
+- PnP.PowerShell - Required for all SharePoint Online operations
+  - Location: Installed via `Install-Module PnP.PowerShell`
+  - Used for: Site enumeration, permissions scanning, storage metrics, file search, templating, bulk operations
+  - Connection: Interactive authentication via Azure AD App (ClientId required)
+
+**Infrastructure:**
+- System.Windows.Forms - Desktop UI framework
+- System.Drawing - UI graphics and rendering
+- Microsoft.SharePoint.Client - Underlying SharePoint CSOM (via PnP.PowerShell)
+
+## Configuration
+
+**Environment:**
+- `Sharepoint_Settings.json` - User preferences (data folder location, language)
+- `Sharepoint_Export_profiles.json` - Saved connection profiles (Tenant URL, Client ID)
+- `Sharepoint_Templates.json` - Site structure templates (captured and reapplied)
+
+**Build:**
+- Single executable: `Sharepoint_ToolBox.ps1`
+- Launched directly: `.\Sharepoint_Toolbox.ps1`
+
+**Localization:**
+- File: `lang/fr.json` - French translations
+- Default: English (en)
+- Loaded dynamically at runtime
+
+## Platform Requirements
+
+**Development:**
+- Windows Operating System (WinForms is Windows-only)
+- PowerShell 5.1+
+- Internet connection for Azure AD authentication
+- Access to SharePoint Online tenant
+
+**Production:**
+- Windows 10/11 (or Windows Server 2016+)
+- PowerShell 5.1 minimum
+- Azure AD tenant with properly configured app registration
+- Network access to target SharePoint Online sites
+
+## Data Persistence
+
+**Local Storage:**
+- JSON files in configurable data folder (default: `Sharepoint_Export_profiles.json`, `Sharepoint_Templates.json`, `Sharepoint_Settings.json`)
+- CSV exports of reports and bulk operation results
+- HTML reports with interactive UI
+
+**No external databases** - All storage is file-based and local
+
+## Authentication
+
+**Method:**
+- Azure AD Interactive Login (user-initiated browser-based auth)
+- Client ID (App Registration ID) required
+- No client secrets or certificates (interactive auth flow only)
+- PnP.PowerShell handles Azure AD token acquisition
+
+## Known Versions
+
+- PowerShell: 5.1 (minimum requirement stated in README)
+- PnP.PowerShell: Not pinned (latest version recommended)
+
+---
+
+*Stack analysis: 2026-04-02*