Sentinel integration — Workspace configuration UI

[TFT444]

Overview

Add a workspace configuration screen to the portal where users can enter their Microsoft Sentinel credentials. The portal falls back to demo data when no workspace is configured.

UI elements

• Settings panel (accessible from TopBar or portal nav)
• Fields: Tenant ID, Subscription ID, Resource Group, Workspace ID, Client ID, Client Secret
• "Test connection" button — validates credentials against Azure AD and returns workspace name on success
• Credentials stored in browser localStorage (never sent to any backend we control)
• Clear visual indicator: "Live mode" (green) vs "Demo mode" (amber) in TopBar

Acceptance criteria

• Settings panel accessible from portal
• All 6 fields present with correct labels and placeholder text
• "Test connection" flow implemented (can be stubbed in demo mode)
• TopBar shows Live/Demo mode indicator
• No credentials logged to console or committed to code

Part of

Epic #118 — Phase 2 Live Sentinel integration