feat: add maturity

[SWvheerden]

Description

add maturity checks to the wallet

[gemini-code-assist]

Code Review

This pull request introduces output maturity tracking and a new 'Locked' transaction status to the wallet. Key changes include a database migration to add a maturity column to the outputs table, updates to balance calculation logic to account for immature funds, and enhancements to the transaction processor to handle time-locked outputs. The code review identified several critical issues: the get_output_totals_for_account function incorrectly includes spent outputs in its aggregates, the get_total_unspent_balance function needs to explicitly exclude locked outputs and ensure outputs are confirmed, and the lock_height calculation for pending transactions fails to consider change outputs.