* security: do not follow directory symlinks in `cargo xtask stats` (CWE-400)
The stats walker descended with `Path::is_dir()`, which follows symlinks, and
kept no record of visited directories. A small acyclic graph of directory
aliases planted in a workspace package (for example through a contribution a
developer inspects) therefore caused exponentially repeated enumeration and file
reads, consuming CPU and I/O far beyond the repository's real size.
`walk` now inspects each entry's own `file_type()` and skips symlinks before
descending or reading, so directory aliases are never re-scanned. A traversal
budget (`MAX_ENTRIES`) bounds total work as defense in depth.
Addresses finding row 4.
* fix: report statistics traversal exhaustion
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Co-authored-by: skylartaylor <26588250+skylartaylor@users.noreply.github.com>
skylartaylor