docs(frontend): Fix HMR configuration example to match actual implementation

The README documentation showed incorrect HMR clientPort configuration using process.env instead of the env variable from loadEnv. Changes: - Update clientPort example to use env.WDS_SOCKET_PORT (not process.env) - Change from falsy coalescing to explicit conditional check - Ensure documentation matches vite.config.js implementation Addresses CodeRabbit feedback on PR #1607. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

Author: hari-kuriakose

frontend/README.md

@@ -323,7 +323,7 @@ server: {
  },
  hmr: {
  port: 3000,
- clientPort: Number(process.env.WDS_SOCKET_PORT) || 3000,
+ clientPort: env.WDS_SOCKET_PORT ? Number(env.WDS_SOCKET_PORT) : 3000,
  },
 }
 ```