Phase 3C: Deployment pipeline & Store-and-Forward engine

Deployment Manager (WP-1–8, WP-16):
- DeploymentService: full pipeline (flatten→validate→send→track→audit)
- OperationLockManager: per-instance concurrency control
- StateTransitionValidator: Enabled/Disabled/NotDeployed transition matrix
- ArtifactDeploymentService: broadcast to all sites with per-site results
- Deployment identity (GUID + revision hash), idempotency, staleness detection
- Instance lifecycle commands (disable/enable/delete) with deduplication

Store-and-Forward (WP-9–15):
- StoreAndForwardStorage: SQLite persistence, 3 categories, no max buffer
- StoreAndForwardService: fixed-interval retry, transient-only buffering, parking
- ReplicationService: async best-effort to standby (fire-and-forget)
- Parked message management (query/retry/discard from central)
- Messages survive instance deletion, S&F drains on disable

620 tests pass (+79 new), zero warnings.

tests/ScadaLink.Commons.Tests/Types/EnumTests.cs

@@ -6,7 +6,7 @@ public class EnumTests
 {
     [Theory]
     [InlineData(typeof(DataType), new[] { "Boolean", "Int32", "Float", "Double", "String", "DateTime", "Binary" })]
-    [InlineData(typeof(InstanceState), new[] { "Enabled", "Disabled" })]
+    [InlineData(typeof(InstanceState), new[] { "NotDeployed", "Enabled", "Disabled" })]
     [InlineData(typeof(DeploymentStatus), new[] { "Pending", "InProgress", "Success", "Failed" })]
     [InlineData(typeof(AlarmState), new[] { "Active", "Normal" })]
     [InlineData(typeof(AlarmTriggerType), new[] { "ValueMatch", "RangeViolation", "RateOfChange" })]