ci: typecheck workflow + badge

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

Author: Ruzylo-cloud

.github/workflows/ci.yml

@@ -0,0 +1,15 @@
+name: CI
+on:
+  push:
+    branches: [main]
+  pull_request:
+jobs:
+  typecheck:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+      - run: npm install --no-audit --no-fund typescript@5 @types/node
+      - run: npx tsc --noEmit -p tsconfig.json

README.md

@@ -1,4 +1,5 @@
 # websocket-client
+![CI](https://github.com/FerrowAI/websocket-client/actions/workflows/ci.yml/badge.svg)
 
 A reconnecting WebSocket wrapper for TypeScript/JavaScript. Exponential
 backoff with jitter, heartbeat ping/pong, a bounded message queue for while
@@ -15,6 +16,7 @@ this library does not bundle one, on purpose (see Design notes).
 ```bash
 npm install websocket-client
 # Node also needs a WebSocket implementation, e.g.:
+![CI](https://github.com/FerrowAI/websocket-client/actions/workflows/ci.yml/badge.svg)
 npm install ws
 ```