fix: separate README for each crate, remove cross-badge confusion

- punkgo-core gets minimal README pointing to punkgo-kernel
- punkgo-kernel README drops punkgo-core badge
- Bump to v0.2.8

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: FeilixX

Cargo.lock

@@ -7,7 +7,7 @@ members = [
 resolver = "2"
 
 [workspace.package]
-version = "0.2.7"
+version = "0.2.8"
 edition = "2024"
 authors = ["Felix <feijiu@punkgo.ai>"]
 license = "MIT"

Cargo.toml

@@ -4,7 +4,6 @@
 
 [![CI](https://github.com/PunkGo/punkgo-kernel/actions/workflows/ci.yml/badge.svg)](https://github.com/PunkGo/punkgo-kernel/actions/workflows/ci.yml)
 [![crates.io](https://img.shields.io/crates/v/punkgo-kernel.svg)](https://crates.io/crates/punkgo-kernel)
-[![crates.io](https://img.shields.io/crates/v/punkgo-core.svg?label=punkgo-core)](https://crates.io/crates/punkgo-core)
 
 > When AI does everything for you, who proves you still exist?
 

README.md

@@ -7,7 +7,7 @@ authors.workspace = true
 license.workspace = true
 repository.workspace = true
 rust-version.workspace = true
-readme = "../../README.md"
+readme = "README.md"
 homepage.workspace = true
 keywords = ["ai", "audit", "merkle", "agent", "accountability"]
 categories = ["cryptography", "development-tools"]

crates/punkgo-core/Cargo.toml

@@ -0,0 +1,13 @@
+# PunkGo Core
+
+[![crates.io](https://img.shields.io/crates/v/punkgo-core.svg)](https://crates.io/crates/punkgo-core)
+
+Core type definitions for [PunkGo](https://punkgo.ai): actors, actions, energy, boundaries, consent, and IPC protocol.
+
+This crate contains no runtime logic — it exists so lightweight consumers (like [punkgo-jack](https://github.com/PunkGo/punkgo-jack)) can depend on protocol types without pulling in the full kernel.
+
+For the full engine, see **[punkgo-kernel](https://crates.io/crates/punkgo-kernel)**.
+
+## License
+
+[MIT](../../LICENSE)

crates/punkgo-core/README.md

@@ -17,7 +17,7 @@ default = []
 testkit = []
 
 [dependencies]
-punkgo-core = { path = "../punkgo-core", version = "0.2.7" }
+punkgo-core = { path = "../punkgo-core", version = "0.2.8" }
 anyhow.workspace = true
 async-trait.workspace = true
 serde.workspace = true