Checking PR #29930: attr: update to 2.6.0 (Formalities Audit)

✅ Pull request originates from a dedicated feature branch (attr)

Commit 9d8ad7b - attr: update to 2.6.0:

✅ Author and committer identities are valid
✅ Commit is not a merge commit
✅ Commit subject layout and length are valid: "attr: update to 2.6.0"
✅ Commit description lines adhere to width formatting rules
✅ Commit contains a consistent and valid 'Signed-off-by:' line
⚠️ Warning: Commit is unsigned or cryptographic signature verification failed (Reason: unsigned). Signing commits is a recommended best practice for verifying identity, but is not mandatory.