Add two new phases to improve plan quality through user collaboration:
- Phase 0: Idea Refinement - Refines feature ideas through dialogue
before running research agents. Asks questions one at a time,
prefers multiple choice, focuses on purpose/constraints/success
criteria. Skip option for detailed descriptions.
- Research Validation - After research completes, summarizes findings
and validates alignment before drafting the full plan.
Both phases are optional and can be skipped, ensuring the workflow
remains lightweight while catching misunderstandings early.
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