feat(auth): add opt-in shared context groups across accounts

tests/unit/auth-command-args.test.ts

@@ -0,0 +1,34 @@
+import { describe, expect, it } from 'bun:test';
+import { parseArgs } from '../../src/auth/commands/types';
+
+describe('auth command args parsing', () => {
+  it('parses create with explicit shared context', () => {
+    const parsed = parseArgs(['work', '--share-context']);
+
+    expect(parsed.profileName).toBe('work');
+    expect(parsed.shareContext).toBe(true);
+    expect(parsed.contextGroup).toBeUndefined();
+  });
+
+  it('parses context group with separate value', () => {
+    const parsed = parseArgs(['work', '--context-group', 'sprint-a']);
+
+    expect(parsed.profileName).toBe('work');
+    expect(parsed.shareContext).toBe(false);
+    expect(parsed.contextGroup).toBe('sprint-a');
+  });
+
+  it('parses context group with equals form', () => {
+    const parsed = parseArgs(['--context-group=sprint-a', 'work']);
+
+    expect(parsed.profileName).toBe('work');
+    expect(parsed.contextGroup).toBe('sprint-a');
+  });
+
+  it('flags missing context group value as empty string', () => {
+    const parsed = parseArgs(['work', '--context-group']);
+
+    expect(parsed.profileName).toBe('work');
+    expect(parsed.contextGroup).toBe('');
+  });
+});