Replace the custom dot-path walking implementation (SplitWithEscaping +
WalkSegments) in the proxy service's JWT middleware with
github.com/jmespath-community/go-jmespath. extractRoles in oidcroles.go
and readUserIDClaim in account_resolver.go now uses jmespath.Search()

NOTE: This change is backwards-incompatible for some corner cases. While
simple dot-separated paths like 'realm_access.roles' are unchanged,
claim paths containing literal dots (i.e. where the dot does not
indicate a hierarchy) must now be quoted ('"sub.roles"' instead of
'sub\.roles').