Remove publishability docs and add CI badges

Delete transitional planning docs (PUBLISHABILITY_ROADMAP.md and docs/API.md), tidy Cargo.toml excludes (remove roadmap, add AGENTS.md), and update documentation. Add crates.io/docs.rs/CI badges to README, remove the API.md link from docs/README.md, and add a CI Coverage section to docs/TESTING.md documenting the CI jobs and feature-matrix checks.

Author: swgiacomelli

Cargo.toml

@@ -20,8 +20,8 @@ exclude = [
     "target/",
     "apps/",
     "xtask/",
+    "AGENTS.md",
     "CLAUDE.md",
-    "PUBLISHABILITY_ROADMAP.md",
     "Cargo.toml.orig",
 ]
 

PUBLISHABILITY_ROADMAP.md

@@ -1,5 +1,9 @@
 # ph-esp32-mac
 
+[![Crates.io](https://img.shields.io/crates/v/ph-esp32-mac.svg)](https://crates.io/crates/ph-esp32-mac)
+[![Docs.rs](https://docs.rs/ph-esp32-mac/badge.svg)](https://docs.rs/ph-esp32-mac)
+[![CI](https://github.com/photon-circus/ph-esp32-mac/actions/workflows/ci.yml/badge.svg)](https://github.com/photon-circus/ph-esp32-mac/actions/workflows/ci.yml)
+
 `ph-esp32-mac` is a `no_std`, `no_alloc` Rust driver for the ESP32 Ethernet MAC (EMAC). It targets ESP32 hardware, provides LAN8720A PHY support, and integrates with smoltcp, embassy-net, and esp-hal.
 
 ---