[BUG] [Mission Profile] - Save Draft button provides no success/error feedback -- user cannot confirm save

## Bug Description

The Mission and Purpose profile section Save Draft button provides no visible feedback after click - no success toast, no error message, no status badge update, no loading spinner. User has no confirmation whether the save succeeded or failed.

## Steps to Reproduce

1. Navigate to /systems/92afdc15-bc6f-4648-8073-ad6af396cf97/mission-purpose
2. Fill in Mission Statement, Business Purpose, and Operational Justification fields
3. Click Save Draft button
4. Observe: page scrolls slightly but no toast notification, no visual feedback, status badge remains NotStarted

## Expected Behavior

- On success: green toast notification "Draft saved successfully" (or similar)
- Status badge updates from "NotStarted" to "Draft"
- On failure: red toast/error message with description

## Actual Behavior

- Button click appears to fire (no JS error in console)
- No toast notification appears
- No status change visible
- No loading/spinner on the button
- User cannot determine if save was successful

## Console Errors

No JS errors captured in console. Silent UI -- save may be succeeding server-side but UI gives no acknowledgment.

## Browser/Environment

Azure Container Apps Dashboard v2
Browser: Chromium (Playwright/Hermes browser)
Date: 2026-07-05T06:40:00Z
Sweep: Automated 4-hour QA sweep

Filed by Oracle -- Automated 4-hour QA Sweep 2026-07-05T06:40:00Z