docs: add feature status audit design

Design for classifying 3394 unknown features against their .NET
implementations in batches of 50, using PortTracker batch-update
with mandatory dry-run before execution.

docs/plans/2026-02-27-feature-status-audit-design.md

@@ -0,0 +1,106 @@
+# Feature Status Audit Design
+
+**Date:** 2026-02-27
+**Status:** Approved
+
+## Problem
+
+3394 features in module 8 (`server`) are marked as `unknown` status after a bulk reclassification. Each needs to be checked against its .NET implementation to determine the correct status.
+
+## Scope
+
+- **Module:** 8 (server) — all 3394 unknown features
+- **Go source files:** 64 distinct files
+- **All features have `dotnet_class` and `dotnet_method` mappings** — no unmapped features
+
+## Classification Criteria
+
+| Status | Criteria | Example |
+|--------|----------|---------|
+| `verified` | .NET method exists with non-trivial logic matching Go behavior | `MemStore.StoreRawMsg` — full implementation |
+| `stub` | .NET method exists but is `throw new NotImplementedException()`, empty, or only partially implemented | `FileStore.Compact` — no real logic |
+| `n_a` | Go feature doesn't apply to .NET — .NET uses a different approach (different library, runtime feature, or platform pattern) | Go logging functions → .NET uses `Microsoft.Extensions.Logging` |
+| `deferred` | .NET method doesn't exist, or classification requires running the server end-to-end | Server-integration features needing full runtime |
+
+**Partial implementations** (method exists with some logic but missing significant functionality) are classified as `stub`.
+
+## Batch Execution Process
+
+Features are processed in fixed batches of 50. Each batch follows this workflow:
+
+### Step 1: Fetch next 50 unknown features
+
+```bash
+dotnet run --project tools/NatsNet.PortTracker -- feature list --module 8 --status unknown --db porting.db
+```
+
+Take the first 50 IDs from the output.
+
+### Step 2: Inspect .NET source for each feature
+
+For each feature:
+1. Read the `dotnet_class` and `dotnet_method` from the feature record
+2. Find the .NET source file containing that class
+3. Check the method body:
+   - Real logic matching Go = `verified`
+   - Stub / empty / partial = `stub`
+   - .NET alternative exists = `n_a`
+   - Method not found = `deferred`
+
+### Step 3: Dry-run the batch update (MANDATORY)
+
+Group features by their determined status and dry-run using PortTracker:
+
+```bash
+# Dry-run — verify correct features affected
+dotnet run --project tools/NatsNet.PortTracker -- feature batch-update --ids 150-160 --set-status deferred --db porting.db
+dotnet run --project tools/NatsNet.PortTracker -- feature batch-update --ids 2068-2077 --set-status verified --db porting.db
+```
+
+Review the preview output. Only proceed if the listed features match expectations.
+
+### Step 4: Execute once dry-run verified
+
+```bash
+dotnet run --project tools/NatsNet.PortTracker -- feature batch-update --ids 150-160 --set-status deferred --execute --db porting.db
+dotnet run --project tools/NatsNet.PortTracker -- feature batch-update --ids 2068-2077 --set-status verified --execute --db porting.db
+```
+
+### Step 5: Verify remaining count
+
+```bash
+dotnet run --project tools/NatsNet.PortTracker -- feature list --status unknown --db porting.db
+```
+
+Confirm the count decreased by ~50.
+
+## Rules
+
+1. **ALWAYS dry-run before executing** — no exceptions
+2. **NEVER use direct SQL** (`sqlite3`) — use PortTracker CLI exclusively
+3. **Process exactly 50 per batch** (or fewer if fewer remain)
+4. **Report classification breakdown** after each batch (e.g. "Batch 3: 12 verified, 30 stub, 3 n_a, 5 deferred")
+5. **68 batches total** (3394 / 50 = ~68)
+
+## Key .NET Source Locations
+
+```
+dotnet/src/ZB.MOM.NatsNet.Server/
+  Accounts/Account.cs, AccountResolver.cs, DirJwtStore.cs
+  Auth/AuthHandler.cs, JwtProcessor.cs
+  Config/ReloadOptions.cs, ServerOptionsConfiguration.cs
+  JetStream/MemStore.cs, FileStore.cs, JetStreamTypes.cs
+  JetStream/NatsStream.cs, NatsConsumer.cs, RaftTypes.cs
+  Protocol/ProtocolParser.cs, ProxyProtocol.cs
+  Routes/RouteTypes.cs, LeafNode/LeafNodeTypes.cs, Gateway/GatewayTypes.cs
+  Mqtt/MqttHandler.cs, WebSocket/WebSocketTypes.cs
+  Internal/ (various data structures)
+  NatsServer.cs, NatsServer.*.cs (partial class files)
+  ClientConnection.cs
+```
+
+## Non-Goals
+
+- No code changes — this is classification only
+- No unit_tests reclassification (separate effort)
+- No schema changes needed (`unknown` already added)