docs: add versioning convention to naming doc

X.Y.Z semver: Z=bugfix, Y=minor feature, X=major/breaking

notes/naming-convention.org

@@ -12,6 +12,16 @@
 
 cl-tty is the first harvested library of the Stoa cannibalization pipeline — a pure-CL terminal I/O library, independent of any project.
 
+* Versioning Convention
+
+All projects follow strict semver: X.Y.Z where:
+- **X** — major release (architecture-breaking changes)
+- **Y** — minor release (new features, backwards-compatible)
+- **Z** — patch release (bug fixes only, no new features)
+
+Feature releases increment Y. Bugfix and hardening releases increment Z.
+No feature release ships without its prerequisite hardening releases resolved.
+
 * Identity Architecture
 
 | Name | Greek | Layer | Role |