[FEATURE] Per-workspace / per-project account support in VS Code extension and terminal

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When working across multiple projects or clients, I often need to use different Anthropic accounts (e.g., personal vs. work, or different client accounts). Currently, Claude Code always uses a single globally configured account, which makes it impossible to:

• Use a work account for one workspace and a personal account for another
• - Manage different billing contexts per project/client
• - - Switch accounts without re-authenticating globally

This affects both the VS Code extension and the terminal CLI.

Proposed Solution

Add per-workspace (per-project) account configuration support:

VS Code Extension:

• Allow setting a Claude Code account in .vscode/settings.json or a .claude config file at the workspace root
• - The extension should use the workspace-level account when set, falling back to the global account

Terminal CLI:

• Support a --account flag or an environment variable (e.g., CLAUDE_ACCOUNT) to specify which account to use per session
• - Allow a .claude config file at the project root to specify the account (similar to how .nvmrc works for Node.js versions)

Account management:

• Provide a command to list and manage saved accounts (claude accounts list, claude accounts add, etc.)
• - Store credentials securely per named account profile

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_