Add type-location map and DRY measurement docs
Added a "Type-Location Map" to the plugin README for quick type lookup. Updated MEASUREMENT.md to reference canonical definitions in DOMAIN_MODEL.md for shared measurement logic, reducing duplication. Clarified pallet weighing workflow and fixed the client app doc path. Minor formatting and clarity improvements.
- Restructured documentation: added `docs/README.md` to each sub-project, moved LOGGING and SIGNALR docs into dedicated subfolders with their own `README.md`.
- Updated all cross-references to use new topic folder paths and canonical AyCode.Core doc locations.
- Updated `.csproj` files to auto-include all Markdown docs and project-level `README.md` files.
- Removed obsolete single-file docs, replaced with structured content in topic folders.
- Enforced AI Agent Protocol: session setup, output prefix, no-re-read, and mandatory `docs-check` skill after code changes.
- Added domain-critical reminders and navigation guidance to relevant `README.md` files.
Added detailed documentation: ARCHITECTURE.md, CONVENTIONS.md, GLOSSARY.md, and copilot-instructions.md for Mango.Nop.Core, Data, and Services. Updated/added README.md files for all Mango.Nop libraries and the FruitBank nopCommerce plugin, clarifying structure, key types, and usage. Switched appsettings.json connection string from production to development database. These changes improve developer onboarding and enforce architectural consistency.