v0.6.1-rc.5

This Release:

Applies a fix to detect when the requested amount is within the spendable balance and automatically calculates the fee as if sending all available funds, while retaining the anchor channel reserve. Previously, when users try to calculate fees for amounts close or equal to their total balance, calculate_total_feewould throwInsufficientFunds`.

• Detect near-full-balance send attempts and apply max-spend logic
• Avoids InsufficientFunds error in calculate_total_fee when near the total spendable balance