docs: Fix version formatting in logs and add agent guidelines

Author: rickhohler

AGENTS.md

@@ -0,0 +1,4 @@
+# Agent Guidelines
+
+## Release Management
+- **Tagging**: Always use a leading "v" for release tags (e.g., `v1.0.0`, `v1.1.0`).

CHANGELOG.md

@@ -37,7 +37,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fixed compiler warnings in `MergerTests` regarding `Sendable` conformance and unnecessary `await`
 - Fixed type mismatch errors in `HashComputationTests`
 
-## [1.3.0] - 2025-12-12
+## [v1.3.0] - 2025-12-12
 
 ### Changed
 - Bumped version to 1.3.0