feat: in-timer event registration with image upload via Flask Blueprint page

[agent01baarathi]

Overview

Replace the current flow (where race directors must visit rhcloudlink.com to register) with a self-contained registration experience inside RotorHazard itself.

User Flow

1. Race director installs the CloudLink plugin
2. On the Format page, the CloudLink panel shows:
   • Enable/Disable toggle
   • Event ID (read-only once registered)
   • Private Key (read-only once registered)
   • "Setup / Register Event" button → opens /cloudlink/setup
3. On the setup page, race director fills in:
   • Event name, date, city, country, description
   • Image selection (3 options):
     • Use RotorHazard logo (default)
     • Upload a file from the timer machine
     • Enter a URL
4. On submit → CloudLink API registers the event → returns Event ID + Private Key
5. Keys are automatically saved to RH options → panel updates instantly

Implementation

• Flask Blueprint registered via rhapi.ui.blueprint_add() at route /cloudlink/setup
• Custom HTML page styled to match RotorHazard's UI
• Image upload uses presigned S3 URL flow (Pi uploads direct to S3)
• RotorHazard logo available at /static/image/RotorHazard Logo.svg

Phases

• Phase 1 (this issue): Full UI + Blueprint page working with mock API
• Phase 2: Wire up real API endpoints (separate issue)

Related

• API issue: vikibaarathi/RH-Cloud-Link-MS