fix: remove version checks on all commands

[mbevc1]

Some CI systems (like GHA) were multiplexing stdErr/stdOut and polluting output when piping or using output from CLI. This removes checking for version on all commands and only does it when explicitly running --version

[claude]

Claude finished @mbevc1's task in 2m 7s —— View job

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PR Review: Remove version checks on all commands

• Run static analysis (build, vet, mod tidy)
• Read and analyze changed files
• Review code quality and correctness
• Post review feedback

Static Analysis

All green — go build, go vet, and go mod tidy pass with no issues.

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Summary

Clean, well-scoped change. The PR removes the background version-check goroutine from PersistentPreRunE and the PersistentPostRun hook that consumed it. After this PR, update checks only fire for kosli version (in version.go:52) and kosli --version (in main.go:61). This directly addresses the CI stdout/stderr pollution problem described in the PR body.

What's Good

• Correct diagnosis and fix — the background goroutine wrote to stderr in PersistentPostRun, which can interleave with stdout in CI environments that mux the two streams. Removing it from every command is the right fix.
• Existing guardrails preserved — the kosli version subcommand and --version flag paths are untouched, so interactive users still get the upgrade notice when they explicitly ask for the version.
• Tests updated correctly — the renamed TestVersionNoticeNotShownOnRegularCommands test now asserts both json and table output formats produce no update notice, which matches the new behavior. The TestVersionFlagPrintsNotice test still validates the --version path.
• No dead code left behind — the updateNoticeCh channel, the goroutine, and the PersistentPostRun hook are all removed together. All imports in root.go are still used.

Potential Issues

1. Loss of proactive upgrade notices for interactive users — Previously, a user running e.g. kosli list flows at a terminal would see an unobtrusive "new version available" notice on stderr. That's now gone for all commands except explicit version queries. This is a deliberate trade-off (CI correctness > interactive convenience), but worth noting for the team. If you want to bring back the notice for TTY-attached sessions in the future, a isatty(stderr) guard would be a targeted approach.

2. No KOSLI_DISABLE_UPDATE_CHECK opt-out cleanup — The existing KOSLI_DISABLE_UPDATE_CHECK env var (checked in internal/version/update_check.go) is still referenced and tested. Since the check no longer runs on regular commands, the env var now only affects kosli version / --version. That's fine, but the env var documentation (if any) may need updating to reflect the narrower scope.

Verdict

LGTM — the change is minimal, correct, and well-tested. The CI pollution fix is a clear improvement.