stop all work on text regex, ngra text regex is now frozen

ReadMe.md

@@ -34,12 +34,24 @@ Numerics and linear algebra built on top of the core library:
 
 Nitload General Regular Analysis (NGRA) infrastructure for recognizing and processing regular languages:
 
-- **Regex/Automata Core**: Regular expression processing and automata utilities
+- **NFA Direction**: Planned generic ε-NFA sequence execution, followed by weighted automata and NGRA-Tensor research
 - **Parsing Primitives**: Reusable tokenizer and grammar building blocks
 - **Analysis Pipeline**: Structured processing for language-like inputs
 
 NGRA is a foundation for higher-level language tooling. It does not replace `Nitload.Script`; the planned Script implementation depends on NGRA and has not started yet. The source currently under `Nitload.Script` is retained from the earlier EXPRESS implementation and is not part of the active core solution.
 
+The former Text Regex parser, matcher, and source generator are [archived](src/Nitload.RegularAnalysis/Legacy/README.md)
+and excluded from compilation. Generic AST and token infrastructure remain active.
+
+Although Text Regex development is frozen, it produced valuable reusable results: the five-link
+AST model, tree normalization and merging techniques, token/analysis infrastructure, and practical
+experience with COUNT continuations, group boundaries, and rollback. These results remain available
+to inform the new NFA architecture.
+
+Future string-regex functionality will use .NET `GeneratedRegex`. NGRA will no longer pursue
+custom `Span<char>` or SIMD optimizations for string matching; its research focus is generalized
+sequence analysis and, later, weighted relation networks.
+
 ### Nitload.Graphics
 
 Managed graphics infrastructure built on Common and Mathematics: