feat: Implement Phase 1 - SharpCoreDB.Provider.Sync skeleton project

Author: MPCoreDeveloper

docs/proposals/ADD_IN_PATTERN_SUMMARY.md

@@ -0,0 +1,181 @@
+# SharpCoreDB.Provider.Sync — Add-In Pattern Updates
+
+**Date:** 2025-01  
+**Status:** Implementation plans updated to follow add-in pattern
+
+---
+
+## What Changed
+
+The Dotmim.Sync provider implementation plan was updated to follow the **add-in pattern** established by `SharpCoreDB.Provider.YesSql`. This ensures consistency across the SharpCoreDB ecosystem and enables proper NuGet packaging and dependency injection.
+
+### Project Naming
+
+| Before | After | Reason |
+|---|---|---|
+| `SharpCoreDB.Sync` | `SharpCoreDB.Provider.Sync` | Consistent with YesSql/other provider naming |
+| `SharpCoreDB.Sync.Tests` | `SharpCoreDB.Provider.Sync.Tests` | Follows standard test project naming |
+
+### Package Identity
+
+| Aspect | Value |
+|---|---|
+| **NuGet Package ID** | `SharpCoreDB.Provider.Sync` |
+| **Assembly Name** | `SharpCoreDB.Provider.Sync` |
+| **Namespace** | `SharpCoreDB.Provider.Sync` |
+| **Version** | `1.0.0` (independent from core) |
+
+### Dependency Injection Integration
+
+Added formal DI extension pattern:
+
+```csharp
+// Program.cs
+services.AddSharpCoreDBSync(
+    connectionString: "Path=C:\\data\\local.scdb;Password=secret",
+    options: opts => {
+        opts.EnableAutoTracking = true;
+        opts.TombstoneRetentionDays = 30;
+    });
+
+// Later in code
+var provider = serviceProvider.GetRequiredService<SharpCoreDBSyncProvider>();
+```
+
+### Project Structure
+
+**New folders in `src/SharpCoreDB.Provider.Sync/`:**
+
+```
+Extensions/
+  ├─ SyncServiceCollectionExtensions.cs    ← DI registration
+  └─ SyncProviderFactory.cs                 ← Factory pattern
+```
+
+These follow the Microsoft.Extensions.DependencyInjection conventions.
+
+### Documentation Updates
+
+1. **Phase 1.4**: Detailed DI extension implementation task with:
+   - Service registration pattern
+   - Configuration options
+   - Usage examples
+
+2. **Phase 6.2**: README updated to show:
+   - Installation via NuGet
+   - DI setup in Program.cs
+   - Multi-tenant filtering
+   - Sample code
+
+3. **Phase 6.5**: Main README now links to:
+   - `SharpCoreDB.Provider.Sync` package
+   - DI integration examples
+
+### Technical Decisions
+
+Added to TD log:
+
+| TD | Decision | Rationale |
+|---|---|---|
+| TD-7 | Add-in pattern (SharpCoreDB.Provider.Sync) | Consistent with YesSql; enables optional installation |
+| TD-8 | Use DI for provider factory | Microsoft.Extensions.DependencyInjection pattern |
+
+### Milestones
+
+Added new M2 milestone:
+
+| M2 | DI Integration Works | `services.AddSharpCoreDBSync()` registers and resolves from container | Week 2 |
+
+### Risk Mitigations
+
+Added to risk register:
+
+- **DI container misconfiguration** — Comprehensive examples, XML docs, sample project
+
+---
+
+## Alignment with Existing Providers
+
+### SharpCoreDB.Provider.YesSql Pattern
+
+```csharp
+services.AddYesSqlDataStore(c => 
+    c.UseSqlite("Data Source=..." /* ... */));
+
+// SharpCoreDB.Provider.Sync follows the same pattern:
+services.AddSharpCoreDBSync("Path=C:\\...;Password=...");
+```
+
+### Benefits of Add-In Pattern
+
+✅ **Consistency** — Matches the ecosystem's provider model  
+✅ **Optional** — Users choose to install only what they need  
+✅ **Composable** — Integrates naturally with DI containers  
+✅ **Discoverable** — Clear `SharpCoreDB.Provider.*` naming  
+✅ **Versioning** — Independent versioning from core (core v1.3.5 ≠ provider v1.0.0)  
+✅ **Packaging** — Proper separation of concerns for NuGet
+
+---
+
+## File References
+
+- **Updated:** `docs/proposals/DOTMIM_SYNC_IMPLEMENTATION_PLAN.md`
+  - Phase 1.1: Project structure (add-in naming)
+  - Phase 1.4: DI extensions task (new/expanded)
+  - Phase 4: Test project paths updated
+  - Phase 6: NuGet metadata and README examples
+  - Technical decisions: Added TD-7, TD-8
+
+- **Updated:** `docs/proposals/DOTMIM_SYNC_PROVIDER_PROPOSAL.md`
+  - Section 8: Project structure (add-in pattern)
+  - Dependencies: Unchanged
+  - Risks: Added DI misconfiguration mitigation
+
+---
+
+## Implementation Impact
+
+### Phase 1 (Week 2)
+
+Task 1.4 now includes implementing:
+- `SyncServiceCollectionExtensions.cs` with `AddSharpCoreDBSync()` method
+- `SyncProviderFactory.cs` for instance creation
+- Configuration options class (`SyncProviderOptions`)
+
+### Phase 6 (Week 8-9)
+
+NuGet packaging now includes:
+- Package ID: `SharpCoreDB.Provider.Sync`
+- Multi-RID support (standard across all providers)
+- Proper dependencies and metadata
+
+### Documentation
+
+README examples now show DI-first approach:
+```csharp
+// Instead of manual instantiation:
+var provider = new SharpCoreDBSyncProvider { ConnectionString = "..." };
+
+// Use DI:
+services.AddSharpCoreDBSync("...");
+var provider = serviceProvider.GetRequiredService<SharpCoreDBSyncProvider>();
+```
+
+---
+
+## No Breaking Changes
+
+These updates are **planning-level changes** — the actual implementation hasn't started yet. When Phase 1 implementation begins, it will follow the add-in pattern from the start, so no breaking changes will occur later.
+
+---
+
+## Next Steps
+
+1. ✅ **Planning**: Both proposal and implementation plan updated (THIS DOCUMENT)
+2. ⏳ **Phase 0**: Execute prerequisite tasks in SharpCoreDB core
+3. ⏳ **Phase 1**: Create `SharpCoreDB.Provider.Sync` project with DI integration
+4. ⏳ **Phase 2-6**: Complete remaining phases per the implementation plan
+
+For questions or clarifications, see the full plans:
+- [DOTMIM_SYNC_PROVIDER_PROPOSAL.md](./DOTMIM_SYNC_PROVIDER_PROPOSAL.md)
+- [DOTMIM_SYNC_IMPLEMENTATION_PLAN.md](./DOTMIM_SYNC_IMPLEMENTATION_PLAN.md)