[FEATURE] autoMemoryDirectory should support local repo storage

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Only supports absolute paths and as such can not easily source control your memory files.

https://github.com/anthropics/claude-code/issues/33535
https://github.com/anthropics/claude-code/issues/34146
https://github.com/anthropics/claude-code/issues/36636

Proposed Solution

Allow setting relative paths or including env vars.

Alternative Solutions

Anything, just make it easy to use.

Priority

High - Significant impact on productivity

Feature Category

Configuration and settings

Use Case Example

1. Save memories
2. Commit memories
3. Share and retain memories

Additional Context

_No response_