feat: complete release readiness work

- consolidate API ownership and remove dead vendor code

- add Stripe billing, learning paths, and public CV hardening

- add migration, recovery, security, audit, and browser gates

JobTrackerApi/Controllers/JobApplicationDtos.cs

@@ -1,4 +1,5 @@
 using JobTrackerApi.Models;
+using JobTrackerApi.Services;
 
 namespace JobTrackerApi.Controllers
 {
@@ -232,7 +233,8 @@ namespace JobTrackerApi.Controllers
         List<string> MatchedKeywords,
         List<string> MissingKeywords,
         List<MatchSectionCoverageDto> SectionCoverage,
-        bool HasEnoughSignal);
+        bool HasEnoughSignal,
+        IReadOnlyList<LearningRecommendationDto> LearningRecommendations);
 
     public sealed record MatchSectionCoverageDto(string Section, int Matched, int Total);
 }