security(lending): Add circuit-breaker on extreme single-block price moves

[nanaf6203-bit]

Pause liquidations for a configurable liveness window if oracle reports > X% deviation within one block. Wire up the existing circuit-breaker trait in contracts/traits/src/circuit_breaker.rs.

[chidumebiodoh123-cloud]

@chidumebiodoh123-cloud has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I'd like to work on this issue because circuit breakers are a critical security mechanism in DeFi lending protocols. Protecting the protocol from extreme single-block oracle price movements helps prevent malicious liquidations, oracle manipulation attacks, and cascading losses during periods of abnormal market volatility. I enjoy working on security-focused features that strengthen protocol resilience while maintaining fair and predictable behavior for users.
Relevant experience
I have experience developing Rust-based smart contracts and DeFi applications, including risk management, oracle integrations, and protocol security controls. I'm familiar with implementing circuit breakers, pause mechanisms, liquidation safeguards, and configurable governance parameters to mitigate market and oracle-related risks. I have also worked with smart contract testing, edge-case analysis, and security-focused development practices to ensure critical protocol functions behave safely under adverse conditions

ℹ️ Repo Maintainers: To accept this application, review their application or assign @chidumebiodoh123-cloud to this issue.

[Spycall]

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

i can work on this task

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Spycall to this issue.

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