Config file bloat: .claude.json grows indefinitely with duplicate MCP server definitions

Description

The ~/.claude.json config file grows excessively large due to MCP server definitions being duplicated for every temporary session.

Current Behavior

• Config file size: 227KB (81,000+ tokens)
• Contains hundreds of duplicate MCP server definitions
• Each /tmp/claude-* session entry includes a full copy of all MCP server configs
• File will continue growing indefinitely with use

Expected Behavior

• MCP server definitions should be stored globally once
• Session-specific overrides stored separately
• Automatic cleanup of old temp sessions
• Config file should remain manageable in size

Impact

• Inefficient file I/O when reading config
• Wasted disk space
• Potential performance degradation over time

Environment

• OS: Linux (WSL2)
• Claude Code CLI
• File location: ~/.claude.json