mbproxy: strip historical phase/wave/plan references from source comments

Comments described the *history* of how the code arrived (phase numbers,
wave IDs, review IDs, dated TODOs) instead of what it does today. That
scaffolding rotted as the codebase evolved. Cleaned 60 source files +
.gitignore; behaviour unchanged (387/387 tests still pass).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

mbproxy/tests/Mbproxy.Tests/Proxy/Supervision/SupervisorTests.cs

@@ -176,13 +176,13 @@ public sealed class SupervisorTests
     // ── Test 4: runtime fault triggers recovery ──────────────────────────────────────────
 
     /// <summary>
-    /// Phase 12 (W3 test gap #4) — replaces the previous placeholder. Genuinely faults
-    /// the running listener mid-life by stopping its underlying <see cref="TcpListener"/>
-    /// via reflection (the only externally-observable hook to force the accept loop's
-    /// <see cref="Socket.AcceptAsync"/> to throw <see cref="ObjectDisposedException"/>).
-    /// The supervisor must observe the fault, transition to <see cref="SupervisorState.Recovering"/>,
-    /// and re-bind on the next Polly attempt — emitting one
-    /// <c>mbproxy.listener.recovered</c> event and bumping <c>RecoveryAttempts</c>.
+    /// Genuinely faults the running listener mid-life by stopping its underlying
+    /// <see cref="TcpListener"/> via reflection (the only externally-observable hook
+    /// to force the accept loop's <see cref="Socket.AcceptAsync"/> to throw
+    /// <see cref="ObjectDisposedException"/>). The supervisor must observe the fault,
+    /// transition to <see cref="SupervisorState.Recovering"/>, and re-bind on the next
+    /// Polly attempt — emitting one <c>mbproxy.listener.recovered</c> event and bumping
+    /// <c>RecoveryAttempts</c>.
     /// </summary>
     [Fact]
     public async Task Supervisor_RuntimeFault_OnRunningListener_RecoversAndRebinds()