Initial import from private SDK repository

Complete .NET SDK for Restate durable execution engine:
- 4 src projects (Restate.Sdk, Generators, Testing, Lambda)
- 3 test projects (262 tests, benchmarks)
- 4 samples (Greeter, Counter, TicketReservation, SignupWorkflow)
- CI/CD workflows, proto definitions, Docker Compose

Verified end-to-end against Restate 1.6.0.

Author: BeshoyHindy

.editorconfig

@@ -0,0 +1,38 @@
+root = true
+
+[*.cs]
+# CA1716: Identifiers should not match keywords — Get/Set/Call are intentional Restate API names
+dotnet_diagnostic.CA1716.severity = none
+
+# CA1000: Do not declare static members on generic types — StateKey<T>.Of() is idiomatic
+dotnet_diagnostic.CA1000.severity = none
+
+# CA5394: Random is insecure — RestateRand uses deterministic seeded Random for replay safety, not security
+dotnet_diagnostic.CA5394.severity = none
+
+# CA1815: Override Equals on value types — Awakeable<T> is not used for equality comparison
+dotnet_diagnostic.CA1815.severity = none
+
+# CA1032: Implement standard exception constructors — TerminalException intentionally requires a message
+dotnet_diagnostic.CA1032.severity = none
+
+# CA1064: Exceptions should be public — ProtocolException is intentionally internal
+dotnet_diagnostic.CA1064.severity = none
+
+# CA2012: Use ValueTasks correctly — false positive on Awakeable creation pattern
+dotnet_diagnostic.CA2012.severity = suggestion
+
+# CA1859: Use concrete types for improved performance — intentional polymorphism in context factory
+dotnet_diagnostic.CA1859.severity = suggestion
+
+# CA1822: Member can be static — Restate handler methods are instance methods invoked by the framework
+dotnet_diagnostic.CA1822.severity = suggestion
+
+# CA1816: Call GC.SuppressFinalize — not needed for test disposables
+dotnet_diagnostic.CA1816.severity = suggestion
+
+# CA1852: Type can be sealed — suggestion level for test/internal types
+dotnet_diagnostic.CA1852.severity = suggestion
+
+# CA1869: Cache JsonSerializerOptions — suggestion level, fine in tests
+dotnet_diagnostic.CA1869.severity = suggestion

.github/workflows/ci.yml

@@ -0,0 +1,56 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    name: Build & Test
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '10.0.x'
+          dotnet-quality: 'preview'
+
+      - name: Restore
+        run: dotnet restore
+
+      - name: Build
+        run: dotnet build --no-restore -c Release
+
+      - name: Test
+        run: dotnet test --no-build -c Release --logger "trx;LogFileName=results.trx"
+
+      - name: Upload test results
+        uses: actions/upload-artifact@v4
+        if: always()
+        with:
+          name: test-results
+          path: '**/results.trx'
+
+  format:
+    name: Format Check
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '10.0.x'
+          dotnet-quality: 'preview'
+
+      - name: Check formatting
+        run: dotnet format --verify-no-changes --verbosity diagnostic

.github/workflows/publish.yml

@@ -0,0 +1,48 @@
+name: Publish
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: read
+
+jobs:
+  publish:
+    name: Pack & Push to NuGet
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '10.0.x'
+          dotnet-quality: 'preview'
+
+      - name: Restore
+        run: dotnet restore
+
+      - name: Build
+        run: dotnet build --no-restore -c Release
+
+      - name: Test
+        run: dotnet test --no-build -c Release
+
+      - name: Pack
+        run: dotnet pack --no-build -c Release -o ./artifacts
+
+      - name: Push to NuGet.org
+        run: dotnet nuget push ./artifacts/*.nupkg --api-key ${{ secrets.NUGET_API_KEY }} --source https://api.nuget.org/v3/index.json --skip-duplicate
+
+      - name: Push symbols to NuGet.org
+        run: dotnet nuget push ./artifacts/*.snupkg --api-key ${{ secrets.NUGET_API_KEY }} --source https://api.nuget.org/v3/index.json --skip-duplicate
+        continue-on-error: true
+
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: nuget-packages
+          path: ./artifacts/*