[FEATURE] Configurable threshold or opt-out for the recurring weekly-limit usage warning

Problem

Once weekly utilization crosses 75%, Claude Code shows a recurring "You've used NN% of your weekly limit - resets in Xd" warning (VS Code extension banner and CLI). For heavy users who routinely spend the last quarter of the window above 75%, this means days of every week with a permanent warning that carries no new information - we already know we are past 75%, and /usage exists for on-demand checks. It pulls attention on every turn while working and is a real productivity drag.

What I checked (as of 2026-07-01)

• No related key in the settings.json schema and no environment variable in the docs (settings.md, env-vars.md).
• The VS Code extension contributes no setting for this (checked contributes.configuration in the extension's package.json, v2.1.197).
• In the webview bundle, the banner renders whenever the rate-limit status is not "allowed" - there is no client-side threshold or config gate, so the 75% flip appears to be server-driven.
• Prior requests were closed without shipping: #1798 (not planned), #17431 (autoclosed).

Request

Any one of these would solve it:

1. A setting or env var to raise the warning display threshold (e.g. show only at >= 95%), or
2. A toggle to suppress non-blocking usage warnings entirely (keeping hard "You've hit your limit" errors), or
3. Making the banner dismissible per rate-limit window (dismiss once, stays hidden until the window resets or the status escalates).

Environment

• Claude Code VS Code extension 2.1.197 (win32-x64), native CLI 2.1.153
• Windows 11 Pro
• Claude subscription with weekly limits