README: drop stale module status from spec line

Was: "graph engine is implemented against spec v0.3.1; the
other modules in the charter are not yet built."

Both halves are stale — version string lags five minors, and
pipeline-utilities, llm-provider, checkpoint, and observability
all shipped across phases 0-6.0. Trim to a single honest line
referencing the new pin; module-by-module status belongs in
CHANGELOG.

Author: chris-colinsky

README.md

@@ -2,7 +2,7 @@
 
 Python reference implementation of [OpenArmature](https://github.com/LunarCommand/openarmature-spec) — a workflow framework for LLM pipelines and tool-calling agents.
 
-**Status:** alpha. The graph engine module is implemented against spec v0.3.1; the other modules in the charter are not yet built.
+**Status:** alpha. Implemented against spec v0.8.2.
 
 ## Install