TeamCreate records wrong leadSessionId in config.json

Bug

The leadSessionId field written to ~/.claude/teams/<team>/config.json does not match the calling session's actual UUID. This makes cross-session team lookup unreliable.

Steps to Reproduce

1. Confirm current session UUID (e.g., via ~/.claude/sessions/<pid>.json → "sessionId": "44a5bd90-...")
2. Call TeamCreate(team_name: "my-team", description: "test")
3. Read ~/.claude/teams/<assigned-name>/config.json
4. Observe: "leadSessionId": "1ecd8655-..." — different from the actual session UUID

Expected Behavior

leadSessionId should match the session UUID of the caller.

Actual Behavior

leadSessionId is a different UUID (possibly a parent session, pre-compaction UUID, or stale cache value).

Impact

• Cross-session team lookup (filter config.json by leadSessionId == $CLAUDE_SESSION_ID) returns wrong results
• Any team registry design that relies on session attribution is broken

Environment

• Claude Code CLI
• Observed: 2026-04-08