Refactor WebSocket connectors and add separate entry points for Node and Browser

- Removed exports for NodeWebSocketConnector and BrowserWebSocketConnector from the main index files.
- Created separate entry points for Node and Browser in both ESM and CJS formats.
- Updated package.json to include new paths for Node and Browser modules.
- Added new TypeScript declaration files for Node and Browser.
- Created new source files for Node and Browser connectors.
- Updated rollup configuration to handle multiple entry points.

Author: electricessence