[BUG] /insights fails with EBUSY on current session's metadata file (Windows)

Description

/insights crashes with an EBUSY error because it tries to read the current session's locked metadata file. No insights are shown — the command fails entirely.

Error

Error: EBUSY: resource busy or locked, open 'C:\Users\<user>\.claude\usage-data\session-meta\<session-id>.json'

Expected behavior

/insights should skip any locked session files and still generate the report from the remaining data.

Reproduction

1. Open a Claude Code session on Windows
2. Run /insights
3. Command fails with EBUSY error every time, since the current session always locks its own metadata file

Environment

• Windows 11
• Claude Code CLI