Refactor docs: topic folders, TOON, XCUT, protocol sync
- Migrated all topic documentation into dedicated folders with canonical `README.md`, `ISSUES.md`, and `TODO.md` per topic (e.g., `LOGGING/`, `SIGNALR/`, `BINARY/`, `TOON/`).
- Added comprehensive TOON serializer documentation: design, format, options, attributes, inference, issues, and TODOs.
- Introduced `XCUT` folder for cross-cutting issues and TODOs, with canonical entries and topic cross-references.
- Updated all references and navigation to use new folder-based doc paths; fixed links and clarified doc structure.
- Enhanced AI agent protocol: enforce session skill preloading, `[LOADED_DOCS: ...]` short-name prefix, and mandatory `docs-check` skill for doc/code sync.
- Updated `.csproj` to include all `README.md` files for IDE visibility.
- Improved and clarified SignalR, grid, and project-level documentation.
- Minor code/test tweaks and doc content corrections for consistency.
Replaced all Markdown link syntax in documentation with inline code formatting and consistent relative paths. Updated all cross-references and tables for clarity and uniformity. No code or logic changes; docs only.
- Move all major feature docs (logging, binary, SignalR, DataSource) into per-project `docs/` folders with dedicated Markdown files.
- Split monolithic docs into focused files: `BINARY_FORMAT.md`, `BINARY_FEATURES.md`, `BINARY_OPTIONS.md`, `LOGGING.md`, `LOGGING_SERVER.md`, `LOGGING_REMOTE.md`, `SIGNALR.md`, `SIGNALR_SERVER.md`, `SIGNALR_DATASOURCE.md`.
- Update all references in `README.md`, `copilot-instructions.md`, `GLOSSARY.md`, and `ARCHITECTURE.md` to point to the correct per-project doc.
- Add documentation tables to each project’s `README.md` and clarify folder structure.
- Update `.csproj` files to include `docs/**/*.md` for packaging.
- Remove obsolete/moved docs from the solution file.
- Ensure all technical debt warnings and cross-references are preserved and accurate.
- No code changes; documentation only.
Loretta