Add ability to untrust IPs from the rules view

[TheZupZup]

Summary

This PR adds functionality to remove IPs from the trusted list in the rules view, complementing the existing block/unblock operations.

Key Changes

• Added untrust_ip_in_rules() function in monitor.py to remove IPs from the trusted IPs list in the rules file
• Added new keybinding T in the TUI to trigger the untrust action
• Implemented action_toggle_trust() method in SilentGuardTUI to handle untrusting IPs from the rules view
• Updated help text to document the new T keybinding for untrusting IPs
• Added validation to prevent untrusting blocked IPs (they must be unblocked first)

Implementation Details

• The untrust_ip_in_rules() function mirrors the pattern of unblock_ip_in_rules(), loading rules, removing the IP from the trusted list, and persisting changes
• The action only works in rules view mode and provides appropriate status messages for different scenarios (success, IP not found, blocked IP attempt, invalid selection)
• Status updates include current counts of blocked IPs, trusted IPs, and known processes for user feedback

https://claude.ai/code/session_01CcHv2bypYA1NEgPWB2oWAy