[Feature Request] Add configurable session usage buffer threshold with soft-limit warnings

Bug Description
Feature Request: Session usage limit — ability to reserve a buffer (e.g., 5%)

On the Claude Code Pro plan, each 5-hour session has a usage cap. I often consume nearly the entire cap during deep
analysis tasks, which leaves no headroom for basic session management (checking status, reviewing task lists, etc.).

Requested behavior:
Add a setting that allows users to reserve a small percentage (e.g., 5%) of the session usage limit as a buffer. When
usage reaches the threshold (e.g., 95%), Claude Code would warn the user or soft-limit further large requests, while
still allowing lightweight commands to proceed.

Why it's useful:

• Prevents the frustrating state of being fully blocked mid-session
• Gives users a chance to save work, wrap up gracefully, or switch tasks
• A simple slider or numeric field in settings would suffice

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.78
• Feedback ID: 3a9f2f39-c02f-400e-9c87-01f8d81283e7

Errors

[{"error":"Error: ENOENT: no such file or directory, unlink 'C:\\Users\\yoshi\\AppData\\Local\\Temp\\claude\\C--Users-yoshi-Documents-GitHub-Data-Analytics\\7ecf5e85-e6e9-4b86-a895-ca470bcf3663\\tasks\\ab4268ef38343ce62.output'\n    at async unlink (node:internal/fs/promises:1065:10)\n    at async Hq6 (file:///C:/Users/yoshi/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:272:304)","timestamp":"2026-04-06T12:06:19.600Z"}]