Add regression test for quadratic curve buy and sell quote symmetry

[Chucks1093]

Summary

The quadratic bonding curve preset must satisfy buy and sell quote symmetry: the cost to buy N keys at supply S must equal the proceeds from selling N keys at supply S+N. A regression test should confirm this holds specifically for the quadratic preset.

Scope

• Register a creator with the Quadratic preset
• Get buy quote for N keys at supply S
• Get sell quote for N keys at supply S+N
• Assert both values are equal
• Cover supply levels: 0, 50, and 500

Acceptance Criteria

• Buy quote equals sell quote at corresponding supply levels for all three tested levels
• Symmetry holds for both small and large key amounts

ETA: 12 hours

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[Kappa16]

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PLEASE MAINTAINER ILL LOVE TO WORK ON THIS ISSUE ,PLS ASASIGN

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[Alaka-ibr]

@Alaka-ibr has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, will love to work on this.

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[wheval]

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Hello i would love to work on this.

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[amankoli09]

@amankoli09 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Can i work on this issue PR merge within 1hr

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[grantfox-oss]

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