Connect Milestone component to backend

[lkeegan]

• modify Milestone component to match MilestoneGroupPublic data
• refactor /milestone endpoint to use data from backend
• move lang_id and language from adminStore to langStore
• fix typo in MilestonePublic model
• remove static github pages build now that backend is started to be integrated
• update readme

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0.90909% with 109 lines in your changes missing coverage. Please review.

Project coverage is 15.75%. Comparing base (729220c) to head (314b2b5).

Files with missing lines	Patch %	Lines
frontend/src/lib/components/Milestone.svelte	0.00%	58 Missing and 1 partial ⚠️
frontend/src/lib/client/schemas.gen.ts	0.00%	27 Missing ⚠️
frontend/src/routes/milestone/+page.svelte	0.00%	9 Missing and 1 partial ⚠️
frontend/src/lib/stores/langStore.ts	0.00%	2 Missing and 1 partial ⚠️
...nd/src/lib/components/Admin/MilestoneGroups.svelte	0.00%	2 Missing ⚠️
...tend/src/lib/components/Admin/UserQuestions.svelte	0.00%	2 Missing ⚠️
...ib/components/Admin/EditMilestoneGroupModal.svelte	0.00%	1 Missing ⚠️
...src/lib/components/Admin/EditMilestoneModal.svelte	0.00%	1 Missing ⚠️
.../lib/components/Admin/EditUserQuestionModal.svelte	0.00%	1 Missing ⚠️
frontend/src/lib/components/Admin/Languages.svelte	0.00%	1 Missing ⚠️
... and 2 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #102      +/-   ##
==========================================
+ Coverage   15.67%   15.75%   +0.08%     
==========================================
  Files          93       94       +1     
  Lines        4562     4538      -24     
  Branches      121      122       +1     
==========================================
  Hits          715      715              
+ Misses       3781     3756      -25     
- Partials       66       67       +1     

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud