Phase 9C.1: make clip finding manual-first

[FernandoAbishai]

Summary

• present transcript selection as the primary Create Clips entry
• keep AI discovery available as an explicitly optional secondary path
• preserve speaker-turn shortcut and existing behavior

Scope

Presentation only. No backend, provider, store, schema, or export behavior changes.

Validation

• npm --prefix frontend run test:create-clips-workspace
• npm run smoke:golden-creator-path
• npm --prefix frontend run lint
• npm run build:frontend
• git diff --check

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