Global secrets (e.g. CLAUDE_CODE_OAUTH_TOKEN) are injected as container env
vars at Start() time. Until now, rotating one only propagated to a workspace
on the next full restart-from-zero, which manual ops had to drive via a
`POST /workspaces/:id/restart` loop. Tier-3 Claude Code agents hit the
stale-token path first and surfaced as 401s inside the SDK.
Restart-time re-read of global_secrets + workspace_secrets was already
correct in `provisionWorkspaceOpts` — the missing piece was the trigger.
SetGlobal / DeleteGlobal now enqueue RestartByID for every non-paused,
non-removed, non-external workspace that does NOT shadow the key with a
workspace-level override. Matches the existing behaviour of workspace-scoped
`Set` / `Delete`.
Adds two sqlmock-backed tests exercising both branches.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>