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
Adds a reusable right-click / context menu Blazor component for the AdminUI:
- ContextMenu.razor: right-click surface (browser menu suppressed) + optional
ellipsis fallback trigger, both anchoring the menu at the pointer; keyboard
nav (arrows/Enter/Esc), transparent backdrop outside-click close (no JS).
- ContextMenu.razor.css: scoped styles on the shared theme tokens.
- ContextMenuItem.cs: Label/OnClick/Icon/Disabled/IsSeparator model + Separator().
- Dev demo page at /dev/context-menu-demo.
Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox