chore(release): bump workspace version to 0.2.8

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: easel

Cargo.toml

@@ -17,7 +17,7 @@ members = [
 resolver = "2"
 
 [workspace.package]
-version = "0.2.7"
+version = "0.2.8"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/DocumentDrivenDX/axon"