review(track0): async ContextMenu OnClick + keyboard-⋯ anchoring + focus-return; discovery-driven DriverTypeNames guard; CSV round-trip comment

Wave-0 reviewer findings (no Critical/High):
- T0-1 M: ContextMenuItem.OnClick Action→Func<Task> (kills async-void at menu call sites Wave A/B/C need); keyboard-activated ⋯ now anchors below the button instead of viewport (0,0); focus returns to trigger on close; backdrop closes on native right-click too.
- T0-3 M: guard test now discovers *DriverFactoryExtensions.Register by convention from the deployed driver assemblies instead of a hand-copied list, so a future driver lacking a constant is actually caught.
- T0-2 L: corrected the round-trip 'sole non-round-trippable shape' comment (any table whose final row is a lone empty field).

Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox

tests/Core/ZB.MOM.WW.OtOpcUa.Commons.Tests/Csv/CsvRoundTripTests.cs

@@ -16,10 +16,11 @@ public sealed class CsvRoundTripTests
         // Each case is a jagged table of fields.
         yield return new object[] { new[] { new[] { "a", "b", "c" } } };
         yield return new object[] { new[] { new[] { "a", "b" }, new[] { "c", "d" } } };
-        // NOTE: a single row of a single empty field ([[""]]) is deliberately excluded — it serialises to
-        // the empty string, which is indistinguishable from an empty document and parses back to zero rows.
-        // That one degenerate case is the sole non-round-trippable shape; every multi-field / multi-row
-        // empty case below (",," and blank interior lines) does round-trip exactly.
+        // NOTE: a table whose FINAL row is a single empty field ([[""]], or e.g. [["a"],[""]]) is deliberately
+        // excluded — that trailing lone-empty-field row serialises to nothing after the preceding row's
+        // terminator, so the parser's no-phantom-trailing-row rule drops it on the way back. This is the only
+        // non-round-trippable shape; a single-empty-field row anywhere but last (see the interior [""] case
+        // below), ",,", and blank interior lines all round-trip exactly.
         yield return new object[] { new[] { new[] { "", "", "" } } };
         yield return new object[] { new[] { new[] { "a" }, new[] { "" }, new[] { "b" } } };
         yield return new object[] { new[] { new[] { "a,b", "c" } } };                 // embedded delimiter