Added comprehensive docs for SignalR tag-based dispatch (docs/SIGNALR_ARCHITECTURE.md), including message flow, tag system, dynamic method registry, and tech debt (JSON-in-Binary). Updated all related READMEs, glossaries, and conventions to reference this architecture and clarify grid infrastructure (MgGridBase, FruitBankGridBase) and external dependency locations (AyCode.Core, AyCode.Blazor, Mango.Nop Libraries, FruitBank Plugin). Synchronized solution items and copilot-instructions. Improves discoverability, enforces conventions, and clarifies tech debt for all developers.