502358f7ea
CI's only-new-issues lint surfaced three real items left over from recent additions: - container.go bootstrap snippet had two `fi` shell tokens flagged by dupword. Tagged with the same nolint directive used by the KandevBranchCheckoutPostlude (two distinct shell blocks closing). - DockerExecutor.CreateInstance was 89 lines (over funlen 80). Split the body into helpers: reportCreateInstanceProgress (deferred progress reporter), tryReconnect (gates the resume path), seedSessionDir (per-container auth seed), buildContainerLaunchConfig, and buildCreatedInstance. CreateInstance is now a 30-line top-down orchestrator. - executor_execute.go was 887 effective lines (over revive 800). Move reuseExistingEnvironment + its helpers (latestExecutorRunningForEnv, executorRunningMatchesEnvironment, applyExecutorRunningMetadata, ensureLaunchMetadata) into a sibling executor_environment_reuse.go.