Use the existing self-service authorization helper for policyless regular
users and normalize explicit service-account and STS aliases to their parent.
Keep explicit denials and cross-user authorization intact. Assert decrypted
identity contents and negative boundaries in the existing handler tests.
Adapted from commit 5d0b692d8cd387622a3219e72430dffaaf5a25ce.
Signed-off-by: Feng Ruohang <rh@vonng.com>
Honor self-service authorization denials, prevent session-limited credential delegation and updates, and protect root credential mutations under built-in IAM. Preserve empty-policy inheritance and damaged-account cleanup, normalize new service policy claims at issuance, and add signed Admin API and LDAP regressions.
Signed-off-by: Feng Ruohang <rh@vonng.com>