Problem:
- On first launch, McpRoot::default() created `servers: None`
- McpService::get_all_servers() would incorrectly return error "old structure detected"
- This confused new users who had no legacy MCP data
Root Cause:
- Derived Default trait sets Option<T> fields to None
- New installations should start with v3.7.0 structure immediately
Solution:
- Explicitly implement Default for McpRoot
- Initialize `servers: Some(HashMap::new())` for v3.7.0+ structure
- Legacy fields (claude/codex/gemini) remain empty, only used for deserializing old configs
Impact:
- First-time users get correct v3.7.0 structure immediately
- migrate_mcp_to_unified() correctly detects already-migrated state
- No false "old structure" errors on fresh installs
09f80d82bc