feat(i18n-ko): CLI — human help and TUI chrome #3979

Problem

CLI human help and TUI chrome are effectively en-only in ko. Machine-readable output must stay locale-independent, but human-facing help / pickers / status lines should follow the ko preference.

Desired outcome

Add ko catalog for human-facing CLI/TUI, following #2672 explicit policy:

• Human help: packages/cli/src/cli-ui-locale.ts, onboarding-catalog.ts, tui-primary-guidance, tui-session-status, pi-tui-* pickers/status
• Locale selection: explicit override + system/environment fallback via same resolveSystemUiLocale logic
• Machine output / protocol / JSONL / exit semantics unchanged and locale-independent

Alternatives or workarounds

Keep CLI/TUI in English for ko.

Acceptance criteria

• ko selected → human help / TUI chrome renders Korean; en unchanged
• --locale ko override works; auto follows system ko-KR
• Machine-readable / JSONL output unchanged
• CLI locale-focused suites green

Parent: #3974