ci: add codecov coverage workflow and badge

Author: Yuyz0112

.github/workflows/coverage.yml

@@ -0,0 +1,27 @@
+name: Coverage
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  coverage:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: oven-sh/setup-bun@v2
+        with:
+          bun-version: latest
+
+      - run: bun install
+
+      - run: bun test --coverage --coverage-reporter=lcov
+
+      - uses: codecov/codecov-action@v4
+        with:
+          files: ./coverage/lcov.info
+          fail_ci_if_error: true
+          verbose: true

README.md

@@ -1,5 +1,7 @@
 # openapi-to-skills
 
+[![codecov](https://codecov.io/gh/neutree-ai/openapi-to-skills/graph/badge.svg?branch=main)](https://codecov.io/gh/neutree-ai/openapi-to-skills)
+
 Convert OpenAPI specifications into [Agent Skills](https://agentskills.io/) format - structured markdown documentation that minimizes context size for AI agents.
 
 AI agents often need domain-specific knowledge to complete tasks. Rather than writing custom prompts or building MCP tools from scratch, leveraging existing API documentation is a practical approach - and OpenAPI is the de facto standard with battle-tested specifications maintained over years.