Windows: duplicate CLAUDE.md loaded due to drive letter casing

Description

On Windows, the global ~/.claude/CLAUDE.md file is loaded twice in the same session because the drive letter casing differs between two resolution paths:

1. C:\Users\<user>\.claude\CLAUDE.md (uppercase C:) — resolved by Claude Code itself
2. c:\Users\<user>\.claude\CLAUDE.md (lowercase c:) — resolved by the VSCode extension passing the workspace root

Since Windows paths are case-insensitive, these refer to the same file, but Claude Code treats them as distinct and loads the file twice.

Impact

• ~1.4k tokens wasted per session on duplicate content
• The duplicate appears as two separate entries under Memory Files in /context

Expected Behavior

Claude Code should normalize Windows drive letter casing (or do case-insensitive path comparison) before loading CLAUDE.md files to avoid duplicates.

Environment

• Windows 11 Pro 10.0.26200
• Claude Code v2.1.37
• Running via VSCode extension