feat: Add Paarrot API server with endpoints for controlling app features

- Implemented API server using Express, including endpoints for health check, status, mute, deafen, channel management, and message sending.
- Added middleware for CORS and JSON body parsing.
- Created test scripts (Node.js and Bash) for API endpoint verification.
- Documented API usage and integration in new API documentation files.
- Updated package.json to include necessary dependencies (express, cors, body-parser).

test-api.js

@@ -0,0 +1,91 @@
+#!/usr/bin/env node
+/**
+ * Paarrot API Test Script
+ * 
+ * Simple test script to verify the API server is working.
+ * Run this while Paarrot is running to test the API endpoints.
+ * 
+ * Usage: node test-api.js
+ */
+
+const API_BASE = 'http://127.0.0.1:33384';
+
+async function testEndpoint(name, method, path, body = null) {
+  console.log(`\n🧪 Testing: ${name}`);
+  console.log(`   ${method} ${API_BASE}${path}`);
+  
+  try {
+    const options = {
+      method,
+      headers: {
+        'Content-Type': 'application/json',
+      },
+    };
+    
+    if (body) {
+      options.body = JSON.stringify(body);
+      console.log(`   Body:`, body);
+    }
+    
+    const response = await fetch(`${API_BASE}${path}`, options);
+    const data = await response.json();
+    
+    if (response.ok) {
+      console.log(`   ✅ Success (${response.status})`);
+      console.log(`   Response:`, JSON.stringify(data, null, 2));
+    } else {
+      console.log(`   ❌ Failed (${response.status})`);
+      console.log(`   Error:`, data.error || data);
+    }
+    
+    return data;
+  } catch (error) {
+    console.log(`   ❌ Error:`, error.message);
+    return null;
+  }
+}
+
+async function runTests() {
+  console.log('🚀 Paarrot API Test Suite\n');
+  console.log('Make sure Paarrot is running before running these tests!\n');
+  
+  // Health check
+  await testEndpoint('Health Check', 'GET', '/health');
+  
+  // Get status
+  await testEndpoint('Get Status', 'GET', '/status');
+  
+  // Get channels
+  await testEndpoint('Get Channels', 'GET', '/channels');
+  
+  // Get current room
+  await testEndpoint('Get Current Room', 'GET', '/room/current');
+  
+  // Toggle mute
+  await testEndpoint('Toggle Mute', 'POST', '/mute/toggle');
+  
+  // Set mute
+  await testEndpoint('Set Mute (true)', 'POST', '/mute', { muted: true });
+  await new Promise(resolve => setTimeout(resolve, 500));
+  await testEndpoint('Set Mute (false)', 'POST', '/mute', { muted: false });
+  
+  // Toggle deafen
+  await testEndpoint('Toggle Deafen', 'POST', '/deafen/toggle');
+  
+  // Send message to current room (commented out to avoid spam)
+  // await testEndpoint('Send Message to Current', 'POST', '/message/current', {
+  //   message: 'Test message from API'
+  // });
+  
+  // Test invalid endpoint
+  await testEndpoint('Invalid Endpoint (should 404)', 'GET', '/invalid');
+  
+  console.log('\n✨ Tests complete!\n');
+}
+
+// Run tests if this script is executed directly
+if (require.main === module) {
+  runTests().catch(console.error);
+}
+
+module.exports = { testEndpoint, runTests };