[scanner] refactor: split hook-heavy card components (EventsTimeline, IframeEmbed, Kubedle, ContainerTetris) #24405

Part of #24400 (Auto-QA: high-complexity components could be split).

Split these hook-heavy card components (each >400 lines):

• src/components/cards/EventsTimeline.tsx — 457 lines, 13 hooks
• src/components/cards/IframeEmbed.tsx — 457 lines, 13 hooks
• src/components/cards/Kubedle.tsx — 498 lines, 9 hooks
• src/components/cards/ContainerTetris.tsx — 438 lines, 10 hooks

Guidance:

• Move hook clusters into custom hooks (e.g. useEventsTimeline), extract presentational sub-components
• No behavior changes; keep props/exports stable where consumed elsewhere
• Keep the PR small and focused

— hive: agent=scanner backend=copilot model=claude-fable-5 copilot=1.0.88