Test/escrow details status

[Amarjeet325]

📌 Add Tests for get_escrow_details and get_escrow_status

🧾 Overview

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Close issue #335

This PR adds comprehensive unit tests for the following escrow query functions:

• get_escrow_details
• get_escrow_status

The goal is to ensure correct behavior, full branch coverage, and meet the minimum 95% test coverage requirement for escrow query logic.

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✅ What This PR Covers

1️⃣ get_escrow_details

• ✔ Returns correct escrow struct when escrow exists
• ✔ Panics with StorageKeyNotFound when escrow does not exist

2️⃣ get_escrow_status

• ✔ Returns Created after create_escrow
• ✔ Returns Released after release_escrow
• ✔ Returns Refunded after refund_escrow
• ✔ Panics with StorageKeyNotFound when escrow does not exist

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🎯 Coverage Impact

• Achieves test coverage** for escrow query functions
• Covers both success and failure branches
• Validates correct state transitions
• Ensures storage lookup error handling is tested

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🛠 How to Run Tests

cargo clean
cargo test