fix: #3583216 Backport path prefix handling and same-host SSO skip
Backport of MR 29 (3.x) to 2.0.x:
- Use processInbound() to strip all path prefixes (domain, language) from the referer before building the target URL.
- Skip SSO handshake when source and target domains share the same hostname (session cookies are shared).
Note: the IssueController 'domain' route option change is not backported as domain 2.x does not support this option.
Closes #3583216