[FEATURE] [Coinswap] Add Compute Pool for Taker Crypto Operations

[hulxv]

Description

Integrate compute pool for CPU-intensive cryptographic operations in Taker RPC handlers.

Motivation

Cryptographic operations (signing, verification, key derivation) are CPU-intensive and should not block I/O threads.

Proposed Solution

• Transaction signing
• Signature verification
• Hash computations
• Key derivation
• Contract validation

Tasks

• Identify all CPU-intensive operations
• Mark appropriate handlers with #[rpc_handler(compute)]
• Benchmark performance improvement
• Verify I/O responsiveness maintained
• Document compute pool usage patterns

Expected

• Improved I/O responsiveness
• Better resource utilization
• Performance gains for concurrent operations
• Clear documentation of usage patterns