* fix: resolve concurrency races in RuntimeContext
- getAPIClient: replace check-then-act with sync.OnceValues, matching
the factory_default.go convention; use NewAPIClientWithConfig to avoid
post-construction config override; fall back to direct construction
for test contexts that bypass newRuntimeContext.
- outputErr: guard first-error capture with sync.Once to prevent data
races if Out() is ever called from concurrent goroutines.
Change-Id: I99c94c3dcb7663fa61571c9720163e41a5fc0e36
* fix: use tenant token for auth scopes
Change-Id: I83bb677e9a33e906e207679b2ba8d0364bc20fe3
