Implement auto-approval budget cap for token usage

[olearycrew]

Proposal Summary

Users need a way to automatically stop AI model usage once they've reached a specified budget threshold to prevent unexpected costs.

Additional context

Problem Statement

Developers lack automated controls to limit token expenditure across sessions.

Proposed Solution

Add budget cap setting that allows users to specify a maximum spending limit (e.g., $5, $10, $20). System should track token usage costs and automatically pause AI operations when threshold is reached, with clear notification.

User Impact

Benefits all users, especially those on free tier or with limited budgets.

Implementation Thoughts

• Store budget settings in user preferences
• Add visual indicator of remaining budget in status bar

[olearycrew]

Could be good to inspire this: https://github.com/adamwlarson/RooCodeMicroManager