### What problem does this PR solve?

This PR fixes an issue with the MCP server configuration in RAGFlow's
Docker deployment where:
1. Incorrect parameter naming (`--mcp--host-api-key` with double
hyphens) caused server startup failures
2. Port binding conflicts occurred due to unexposed MCP ports in Docker
3. Inconsistent host addressing between `0.0.0.0` and `127.0.0.1` led to
connectivity issues

The changes ensure proper MCP server initialization and reliable
inter-service communication.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [ ] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [ ] Refactoring
- [ ] Performance Improvement
- [ ] Other (please describe):

### Key Changes

1. **Parameter Correction**:
   - Fixed `--mcp--host-api-key` → `--mcp-host-api-key`