Improve vendor agreement review workflow

[andrewgao2012]

Improves the Commercial Legal vendor agreement review workflow by:

• making deal-breaker handling consistent
• adding an explicit workflow gate before detailed review
• improving customer/vendor orientation
• replacing assumptions about negotiation willingness based on company size with known leverage and constraints
• updating the final review checklist to match the revised counterparty analysis

These changes are intended to reduce contradictory instructions and unsupported assumptions during vendor agreement review.

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