Feature request: allow disabling built-in MCP servers globally / in worktree sessions

Context: Claude Code desktop app on Windows 11. Built-in MCP servers (claude-in-chrome, computer-use, mcp-registry, scheduled-tasks) load their tool name lists and full server instruction blocks into every session's initial context, even when unused.

What I tried:

1. deniedMcpServers in .claude/settings.json — only filters configured servers (user/plugin/managed-mcp.json), not built-ins.
2. Per-project disabledMcpServers in ~/.claude.json — works only for that exact project path; sessions launched in auto-generated git worktrees (<repo>/.claude/worktrees/<name>) get a fresh project key that does not inherit the parent repo's setting.
3. Top-level disabledMcpServers in ~/.claude.json — no effect (verified by observing the initial context of a fresh worktree session).

Request (either would solve it):

• A user-scope (global) way to disable built-in MCP servers, e.g. honor a top-level disabledMcpServers in ~/.claude.json or a settings.json field.
• Worktree sessions inheriting the parent project's disabledMcpServers (worktrees already share permission approvals with the parent).