feat: granular RBAC with resource/operation bindings, users, groups

- Replace admin role with granular roles: view, create, delete, edit, run
- Two binding types: resource bindings (role+resource+optional name) and
  operation bindings (role:run + action like backup, logs, impersonate)
- Name-scoped resource bindings for per-instance access control
- Remove role from project members (all permissions via RBAC)
- Add users, groups, RBAC CRUD endpoints and CLI commands
- describe user/group shows all RBAC access (direct + inherited)
- create rbac supports --subject, --binding, --operation flags
- Backup/restore handles users, groups, RBAC definitions
- mcplocal project-based MCP endpoint discovery
- Full test coverage for all new functionality

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/mcpd/src/services/auth.service.ts

@@ -63,4 +63,32 @@ export class AuthService {
     }
     return { userId: session.userId, expiresAt: session.expiresAt };
   }
+
+  /**
+   * Create a session for a user by email without requiring their password.
+   * Used for admin impersonation.
+   */
+  async impersonate(email: string): Promise<LoginResult> {
+    const user = await this.prisma.user.findUnique({ where: { email } });
+    if (user === null) {
+      throw new AuthenticationError('User not found');
+    }
+
+    const token = randomUUID();
+    const expiresAt = new Date(Date.now() + SESSION_TTL_MS);
+
+    await this.prisma.session.create({
+      data: {
+        token,
+        userId: user.id,
+        expiresAt,
+      },
+    });
+
+    return {
+      token,
+      expiresAt,
+      user: { id: user.id, email: user.email, role: user.role },
+    };
+  }
 }