[7356] Add cookie consent on login page

[n-lark]

Description

See #7356 (comment)

Related Issue(s)

Resolves #7356

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.67%. Comparing base (2c680ad) to head (5035be5).
⚠️ Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
forge/routes/ui/index.js	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7387   +/-   ##
=======================================
  Coverage   76.66%   76.67%           
=======================================
  Files         410      410           
  Lines       20874    20873    -1     
  Branches     5066     5066           
=======================================
  Hits        16004    16004           
+ Misses       4870     4869    -1     

Flag	Coverage Δ
backend	76.67% <0.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.