GHSA-p7fg-763f-g4gf: Claude SDK for TypeScript has Insecure Default File Permissions in Local Filesystem Memory Tool

The Claude SDK for TypeScript had a security flaw where a tool called `BetaLocalFilesystemMemoryTool` created files and folders with overly permissive access settings (using Node.js defaults like `0o666` for files and `0o777` for directories, which control who can read or modify them). This meant that on shared computers or in containerized environments (like Docker), other users could read sensitive agent data or modify it to change how the AI behaves.